From c232286c6b2c1d086a4bd427eabc745635772e02 Mon Sep 17 00:00:00 2001 From: Philip Hazel Date: Mon, 30 Aug 2021 16:59:34 +0100 Subject: [PATCH] Update HTML docs. --- doc/html/pcre2api.html | 9 +- doc/html/pcre2compat.html | 12 +- doc/html/pcre2demo.html | 9 +- doc/html/pcre2pattern.html | 14 +- doc/html/pcre2syntax.html | 9 +- doc/html/pcre2test.html | 28 +- doc/pcre2.txt | 1601 ++++++++++++++++++------------------ doc/pcre2demo.3 | 9 +- doc/pcre2test.txt | 37 +- 9 files changed, 877 insertions(+), 851 deletions(-) diff --git a/doc/html/pcre2api.html b/doc/html/pcre2api.html index 673b465..e625f7f 100644 --- a/doc/html/pcre2api.html +++ b/doc/html/pcre2api.html @@ -1914,6 +1914,13 @@ Extra compile options

The option bits that can be set in a compile context by calling the pcre2_set_compile_extra_options() function are as follows: +

+  PCRE2_EXTRA_ALLOW_LOOKAROUND_BSK
+
+Since release 10.38 PCRE2 has forbidden the use of \K within lookaround +assertions, following Perl's lead. This option is provided to re-enable the +previous behaviour (act in positive lookarounds, ignore in negative ones) in +case anybody is relying on it. 
   PCRE2_EXTRA_ALLOW_SURROGATE_ESCAPES
@@ -4001,7 +4008,7 @@ Cambridge, England.


REVISION

-Last updated: 28 August 2021 +Last updated: 30 August 2021
Copyright © 1997-2021 University of Cambridge.
diff --git a/doc/html/pcre2compat.html b/doc/html/pcre2compat.html index 54fb643..eb82694 100644 --- a/doc/html/pcre2compat.html +++ b/doc/html/pcre2compat.html @@ -153,8 +153,10 @@ letters, regardless of case, when case independence is specified.

16. From release 5.32.0, Perl locks out the use of \K in lookaround -assertions. In PCRE2, \K is acted on when it occurs in positive assertions, -but is ignored in negative assertions. +assertions. From release 10.38 PCRE2 does the same by default. However, there +is an option for re-enabling the previous behaviour. When this option is set, +\K is acted on when it occurs in positive assertions, but is ignored in +negative assertions.

17. PCRE2 provides some extensions to the Perl regular expression facilities. @@ -237,7 +239,7 @@ AUTHOR

Philip Hazel
-University Computing Service +Retired from University Computing Service
Cambridge, England.
@@ -246,9 +248,9 @@ Cambridge, England. REVISION

-Last updated: 06 October 2020 +Last updated: 30 August 2021
-Copyright © 1997-2019 University of Cambridge. +Copyright © 1997-2021 University of Cambridge.

Return to the PCRE2 index page. diff --git a/doc/html/pcre2demo.html b/doc/html/pcre2demo.html index ced324c..7c88bda 100644 --- a/doc/html/pcre2demo.html +++ b/doc/html/pcre2demo.html @@ -234,9 +234,12 @@ pcre2_match_data_create_from_pattern() above. */ if (rc == 0) printf("ovector was not big enough for all the captured substrings\n"); -/* We must guard against patterns such as /(?=.\K)/ that use \K in an assertion -to set the start of a match later than its end. In this demonstration program, -we just detect this case and give up. */ +/* Since release 10.38 PCRE2 has locked out the use of \K in lookaround +assertions. However, there is an option to re-enable the old behaviour. If that +is set, it is possible to run patterns such as /(?=.\K)/ that use \K in an +assertion to set the start of a match later than its end. In this demonstration +program, we show how to detect this case, but it shouldn't arise because the +option is never set. */ if (ovector[0] > ovector[1]) { diff --git a/doc/html/pcre2pattern.html b/doc/html/pcre2pattern.html index 07557bb..2cf4ab4 100644 --- a/doc/html/pcre2pattern.html +++ b/doc/html/pcre2pattern.html @@ -1175,9 +1175,11 @@ For example, when the pattern matches "foobar", the first substring is still set to "foo".

-Perl used to document that the use of \K within lookaround assertions is "not -well defined", but from version 5.32.0 Perl does not support this usage at all. -In PCRE2, \K is acted upon when it occurs inside positive assertions, but is +From version 5.32.0 Perl forbids the use of \K in lookaround assertions. From +release 10.38 PCRE2 also forbids this by default. However, the +PCRE2_EXTRA_ALLOW_LOOKAROUND_BSK option can be used when calling +pcre2_compile() to re-enable the previous behaviour. When this option is +set, \K is acted upon when it occurs inside positive assertions, but is ignored in negative assertions. Note that when a pattern such as (?=ab\K) matches, the reported start of the match can be greater than the end of the match. Using \K in a lookbehind assertion at the start of a pattern can also @@ -3845,16 +3847,16 @@ there is a backtrack at the outer level.

Philip Hazel
-University Computing Service +Retired from University Computing Service
Cambridge, England.


REVISION

-Last updated: 06 October 2020 +Last updated: 30 August 2021
-Copyright © 1997-2020 University of Cambridge. +Copyright © 1997-2021 University of Cambridge.

Return to the PCRE2 index page. diff --git a/doc/html/pcre2syntax.html b/doc/html/pcre2syntax.html index 7383104..cd0599f 100644 --- a/doc/html/pcre2syntax.html +++ b/doc/html/pcre2syntax.html @@ -429,6 +429,9 @@ but some of them use Unicode properties if PCRE2_UCP is set. You can use 

   \K          set reported start of match
+From release 10.38 \K is not permitted by default in lookaround assertions, +for compatibility with Perl. However, if the PCRE2_EXTRA_ALLOW_LOOKAROUND_BSK +option is set, the previous behaviour is re-enabled. When this option is set, \K is honoured in positive assertions, but ignored in negative ones.


ALTERNATION
@@ -682,16 +685,16 @@ delimiter }. To encode the ending delimiter within the string, double it.

Philip Hazel
-University Computing Service +Retired from University Computing Service
Cambridge, England.


REVISION

-Last updated: 28 December 2019 +Last updated: 30 August 2021
-Copyright © 1997-2019 University of Cambridge. +Copyright © 1997-2021 University of Cambridge.

Return to the PCRE2 index page. diff --git a/doc/html/pcre2test.html b/doc/html/pcre2test.html index 617c55c..3e9dd3c 100644 --- a/doc/html/pcre2test.html +++ b/doc/html/pcre2test.html @@ -59,12 +59,7 @@ patterns, and the subject lines specify PCRE2 function options, control how the subject is processed, and what output is produced.

-As the original fairly simple PCRE library evolved, it acquired many different -features, and as a result, the original pcretest program ended up with a -lot of options in a messy, arcane syntax for testing all the features. The -move to the new PCRE2 API provided an opportunity to re-implement the test -program as pcre2test, with a cleaner modifier syntax. Nevertheless, there -are still many obscure modifiers, some of which are specifically designed for +There are many obscure modifiers, some of which are specifically designed for use in conjunction with the test script and data files that are distributed as part of PCRE2. All the modifiers are documented here, some without much justification, but many of them are unlikely to be of use except when testing @@ -89,10 +84,10 @@ names used in the libraries have a suffix _8, _16, or _32, as appropriate.
INPUT ENCODING

Input to pcre2test is processed line by line, either by calling the C -library's fgets() function, or via the libreadline library. In some -Windows environments character 26 (hex 1A) causes an immediate end of file, and -no further data is read, so this character should be avoided unless you really -want that action. +library's fgets() function, or via the libreadline or libedit +library. In some Windows environments character 26 (hex 1A) causes an immediate +end of file, and no further data is read, so this character should be avoided +unless you really want that action.

The input is processed using using C's string functions, so must not @@ -514,11 +509,11 @@ A pattern can be followed by a modifier list (details below).


SUBJECT LINE SYNTAX

-Before each subject line is passed to pcre2_match() or -pcre2_dfa_match(), leading and trailing white space is removed, and the -line is scanned for backslash escapes, unless the subject_literal -modifier was set for the pattern. The following provide a means of encoding -non-printing characters in a visible way: +Before each subject line is passed to pcre2_match(), +pcre2_dfa_match(), or pcre2_jit_match(), leading and trailing white +space is removed, and the line is scanned for backslash escapes, unless the +subject_literal modifier was set for the pattern. The following provide a +means of encoding non-printing characters in a visible way: 

   \a         alarm (BEL, \x07)
   \b         backspace (\x08)
@@ -615,6 +610,7 @@ way pcre2_compile() behaves. See
 for a description of the effects of these options.
 
       allow_empty_class         set PCRE2_ALLOW_EMPTY_CLASS
+      allow_lookaround_bsk      set PCRE2_EXTRA_ALLOW_LOOKAROUND_BSK 
       allow_surrogate_escapes   set PCRE2_EXTRA_ALLOW_SURROGATE_ESCAPES
       alt_bsux                  set PCRE2_ALT_BSUX
       alt_circumflex            set PCRE2_ALT_CIRCUMFLEX
@@ -2126,7 +2122,7 @@ Cambridge, England.
 

 
REVISION

 

-Last updated: 28 August 2021
+Last updated: 30 August 2021
 

 Copyright © 1997-2021 University of Cambridge.
 

diff --git a/doc/pcre2.txt b/doc/pcre2.txt
index b420e22..9291899 100644
--- a/doc/pcre2.txt
+++ b/doc/pcre2.txt
@@ -1877,86 +1877,93 @@ COMPILING A PATTERN
        The option bits that can be set in a compile  context  by  calling  the
        pcre2_set_compile_extra_options() function are as follows:
 
+         PCRE2_EXTRA_ALLOW_LOOKAROUND_BSK
+
+       Since release 10.38 PCRE2 has forbidden the use of \K within lookaround
+       assertions, following Perl's lead. This option is provided to re-enable
+       the previous behaviour (act in positive lookarounds, ignore in negative
+       ones) in case anybody is relying on it.
+
          PCRE2_EXTRA_ALLOW_SURROGATE_ESCAPES
 
-       This  option  applies when compiling a pattern in UTF-8 or UTF-32 mode.
-       It is forbidden in UTF-16 mode, and ignored in non-UTF  modes.  Unicode
+       This option applies when compiling a pattern in UTF-8 or  UTF-32  mode.
+       It  is  forbidden in UTF-16 mode, and ignored in non-UTF modes. Unicode
        "surrogate" code points in the range 0xd800 to 0xdfff are used in pairs
-       in UTF-16 to encode code points with values in  the  range  0x10000  to
-       0x10ffff.  The  surrogates  cannot  therefore be represented in UTF-16.
+       in  UTF-16  to  encode  code points with values in the range 0x10000 to
+       0x10ffff. The surrogates cannot therefore  be  represented  in  UTF-16.
        They can be represented in UTF-8 and UTF-32, but are defined as invalid
-       code  points,  and  cause  errors  if  encountered in a UTF-8 or UTF-32
+       code points, and cause errors if  encountered  in  a  UTF-8  or  UTF-32
        string that is being checked for validity by PCRE2.
 
-       These values also cause errors if encountered in escape sequences  such
+       These  values also cause errors if encountered in escape sequences such
        as \x{d912} within a pattern. However, it seems that some applications,
        when using PCRE2 to check for unwanted characters in UTF-8 strings, ex-
-       plicitly   test   for   the  surrogates  using  escape  sequences.  The
-       PCRE2_NO_UTF_CHECK option does not disable the error that  occurs,  be-
+       plicitly  test  for  the  surrogates  using   escape   sequences.   The
+       PCRE2_NO_UTF_CHECK  option  does not disable the error that occurs, be-
        cause it applies only to the testing of input strings for UTF validity.
 
-       If  the extra option PCRE2_EXTRA_ALLOW_SURROGATE_ESCAPES is set, surro-
-       gate code point values in UTF-8 and UTF-32 patterns no  longer  provoke
-       errors  and are incorporated in the compiled pattern. However, they can
-       only match subject characters if the matching function is  called  with
+       If the extra option PCRE2_EXTRA_ALLOW_SURROGATE_ESCAPES is set,  surro-
+       gate  code  point values in UTF-8 and UTF-32 patterns no longer provoke
+       errors and are incorporated in the compiled pattern. However, they  can
+       only  match  subject characters if the matching function is called with
        PCRE2_NO_UTF_CHECK set.
 
          PCRE2_EXTRA_ALT_BSUX
 
-       The  original option PCRE2_ALT_BSUX causes PCRE2 to process \U, \u, and
-       \x in the way that ECMAscript (aka JavaScript) does.  Additional  func-
+       The original option PCRE2_ALT_BSUX causes PCRE2 to process \U, \u,  and
+       \x  in  the way that ECMAscript (aka JavaScript) does. Additional func-
        tionality was defined by ECMAscript 6; setting PCRE2_EXTRA_ALT_BSUX has
-       the effect of PCRE2_ALT_BSUX, but in addition it  recognizes  \u{hhh..}
+       the  effect  of PCRE2_ALT_BSUX, but in addition it recognizes \u{hhh..}
        as a hexadecimal character code, where hhh.. is any number of hexadeci-
        mal digits.
 
          PCRE2_EXTRA_BAD_ESCAPE_IS_LITERAL
 
-       This is a dangerous option. Use with care. By default, an  unrecognized
-       escape  such  as \j or a malformed one such as \x{2z} causes a compile-
+       This  is a dangerous option. Use with care. By default, an unrecognized
+       escape such as \j or a malformed one such as \x{2z} causes  a  compile-
        time error when detected by pcre2_compile(). Perl is somewhat inconsis-
-       tent  in  handling  such items: for example, \j is treated as a literal
-       "j", and non-hexadecimal digits in \x{} are just ignored, though  warn-
-       ings  are given in both cases if Perl's warning switch is enabled. How-
-       ever, a malformed octal number after \o{  always  causes  an  error  in
+       tent in handling such items: for example, \j is treated  as  a  literal
+       "j",  and non-hexadecimal digits in \x{} are just ignored, though warn-
+       ings are given in both cases if Perl's warning switch is enabled.  How-
+       ever,  a  malformed  octal  number  after \o{ always causes an error in
        Perl.
 
-       If  the  PCRE2_EXTRA_BAD_ESCAPE_IS_LITERAL  extra  option  is passed to
-       pcre2_compile(), all unrecognized or  malformed  escape  sequences  are
-       treated  as  single-character escapes. For example, \j is a literal "j"
-       and \x{2z} is treated as the literal string "x{2z}". Setting  this  op-
+       If the PCRE2_EXTRA_BAD_ESCAPE_IS_LITERAL  extra  option  is  passed  to
+       pcre2_compile(),  all  unrecognized  or  malformed escape sequences are
+       treated as single-character escapes. For example, \j is a  literal  "j"
+       and  \x{2z}  is treated as the literal string "x{2z}". Setting this op-
        tion means that typos in patterns may go undetected and have unexpected
-       results. Also note that a sequence such as [\N{] is  interpreted  as  a
-       malformed  attempt  at [\N{...}] and so is treated as [N{] whereas [\N]
+       results.  Also  note  that a sequence such as [\N{] is interpreted as a
+       malformed attempt at [\N{...}] and so is treated as [N{]  whereas  [\N]
        gives an error because an unqualified \N is a valid escape sequence but
-       is  not supported in a character class. To reiterate: this is a danger-
+       is not supported in a character class. To reiterate: this is a  danger-
        ous option. Use with great care.
 
          PCRE2_EXTRA_ESCAPED_CR_IS_LF
 
-       There are some legacy applications where the escape sequence  \r  in  a
-       pattern  is expected to match a newline. If this option is set, \r in a
-       pattern is converted to \n so that it matches a LF  (linefeed)  instead
-       of  a CR (carriage return) character. The option does not affect a lit-
-       eral CR in the pattern, nor does it affect CR specified as an  explicit
+       There  are  some  legacy applications where the escape sequence \r in a
+       pattern is expected to match a newline. If this option is set, \r in  a
+       pattern  is  converted to \n so that it matches a LF (linefeed) instead
+       of a CR (carriage return) character. The option does not affect a  lit-
+       eral  CR in the pattern, nor does it affect CR specified as an explicit
        code point such as \x{0D}.
 
          PCRE2_EXTRA_MATCH_LINE
 
-       This  option  is  provided  for  use  by the -x option of pcre2grep. It
-       causes the pattern only to match complete lines. This  is  achieved  by
-       automatically  inserting  the  code for "^(?:" at the start of the com-
-       piled pattern and ")$" at the end. Thus, when PCRE2_MULTILINE  is  set,
-       the  matched  line may be in the middle of the subject string. This op-
+       This option is provided for use by  the  -x  option  of  pcre2grep.  It
+       causes  the  pattern  only to match complete lines. This is achieved by
+       automatically inserting the code for "^(?:" at the start  of  the  com-
+       piled  pattern  and ")$" at the end. Thus, when PCRE2_MULTILINE is set,
+       the matched line may be in the middle of the subject string.  This  op-
        tion can be used with PCRE2_LITERAL.
 
          PCRE2_EXTRA_MATCH_WORD
 
-       This option is provided for use by  the  -w  option  of  pcre2grep.  It
-       causes  the  pattern only to match strings that have a word boundary at
-       the start and the end. This is achieved by automatically inserting  the
-       code  for "\b(?:" at the start of the compiled pattern and ")\b" at the
-       end. The option may be used with PCRE2_LITERAL. However, it is  ignored
+       This  option  is  provided  for  use  by the -w option of pcre2grep. It
+       causes the pattern only to match strings that have a word  boundary  at
+       the  start and the end. This is achieved by automatically inserting the
+       code for "\b(?:" at the start of the compiled pattern and ")\b" at  the
+       end.  The option may be used with PCRE2_LITERAL. However, it is ignored
        if PCRE2_EXTRA_MATCH_LINE is also set.
 
 
@@ -1979,16 +1986,16 @@ JUST-IN-TIME (JIT) COMPILATION
 
        void pcre2_jit_stack_free(pcre2_jit_stack *jit_stack);
 
-       These  functions  provide  support  for  JIT compilation, which, if the
-       just-in-time compiler is available, further processes a  compiled  pat-
+       These functions provide support for  JIT  compilation,  which,  if  the
+       just-in-time  compiler  is available, further processes a compiled pat-
        tern into machine code that executes much faster than the pcre2_match()
-       interpretive matching function. Full details are given in the  pcre2jit
+       interpretive  matching function. Full details are given in the pcre2jit
        documentation.
 
-       JIT  compilation  is  a heavyweight optimization. It can take some time
-       for patterns to be analyzed, and for one-off matches  and  simple  pat-
-       terns  the benefit of faster execution might be offset by a much slower
-       compilation time.  Most (but not all) patterns can be optimized by  the
+       JIT compilation is a heavyweight optimization. It can  take  some  time
+       for  patterns  to  be analyzed, and for one-off matches and simple pat-
+       terns the benefit of faster execution might be offset by a much  slower
+       compilation  time.  Most (but not all) patterns can be optimized by the
        JIT compiler.
 
 
@@ -1999,46 +2006,46 @@ LOCALE SUPPORT
        void pcre2_maketables_free(pcre2_general_context *gcontext,
          const uint8_t *tables);
 
-       PCRE2  handles caseless matching, and determines whether characters are
-       letters, digits, or whatever, by reference to a set of tables,  indexed
+       PCRE2 handles caseless matching, and determines whether characters  are
+       letters,  digits, or whatever, by reference to a set of tables, indexed
        by character code point. However, this applies only to characters whose
-       code points are less than 256. By default,  higher-valued  code  points
+       code  points  are  less than 256. By default, higher-valued code points
        never match escapes such as \w or \d.
 
-       When  PCRE2  is  built  with Unicode support (the default), the Unicode
+       When PCRE2 is built with Unicode support  (the  default),  the  Unicode
        properties of all characters can be tested with \p and \P, or, alterna-
-       tively,  the  PCRE2_UCP  option  can be set when a pattern is compiled;
-       this causes \w and friends to use Unicode property support  instead  of
-       the  built-in  tables.  PCRE2_UCP also causes upper/lower casing opera-
-       tions on characters with code points greater than 127  to  use  Unicode
+       tively, the PCRE2_UCP option can be set when  a  pattern  is  compiled;
+       this  causes  \w and friends to use Unicode property support instead of
+       the built-in tables.  PCRE2_UCP also causes upper/lower  casing  opera-
+       tions  on  characters  with code points greater than 127 to use Unicode
        properties. These effects apply even when PCRE2_UTF is not set.
 
-       The  use  of  locales  with Unicode is discouraged. If you are handling
-       characters with code points greater than 127,  you  should  either  use
+       The use of locales with Unicode is discouraged.  If  you  are  handling
+       characters  with  code  points  greater than 127, you should either use
        Unicode support, or use locales, but not try to mix the two.
 
-       PCRE2  contains a built-in set of character tables that are used by de-
-       fault.  These are sufficient for many applications. Normally,  the  in-
-       ternal  tables  recognize only ASCII characters. However, when PCRE2 is
+       PCRE2 contains a built-in set of character tables that are used by  de-
+       fault.   These  are sufficient for many applications. Normally, the in-
+       ternal tables recognize only ASCII characters. However, when  PCRE2  is
        built, it is possible to cause the internal tables to be rebuilt in the
        default "C" locale of the local system, which may cause them to be dif-
        ferent.
 
-       The built-in tables can be overridden by tables supplied by the  appli-
-       cation  that  calls  PCRE2.  These may be created in a different locale
-       from the default.  As more and more applications change to  using  Uni-
+       The  built-in tables can be overridden by tables supplied by the appli-
+       cation that calls PCRE2. These may be created  in  a  different  locale
+       from  the  default.  As more and more applications change to using Uni-
        code, the need for this locale support is expected to die away.
 
-       External  tables  are built by calling the pcre2_maketables() function,
+       External tables are built by calling the  pcre2_maketables()  function,
        in the relevant locale. The only argument to this function is a general
-       context,  which  can  be used to pass a custom memory allocator. If the
+       context, which can be used to pass a custom memory  allocator.  If  the
        argument is NULL, the system malloc() is used. The result can be passed
        to pcre2_compile() as often as necessary, by creating a compile context
-       and calling pcre2_set_character_tables()  to  set  the  tables  pointer
+       and  calling  pcre2_set_character_tables()  to  set  the tables pointer
        therein.
 
-       For  example,  to  build  and  use  tables that are appropriate for the
-       French locale (where accented characters with values greater  than  127
+       For example, to build and use  tables  that  are  appropriate  for  the
+       French  locale  (where accented characters with values greater than 127
        are treated as letters), the following code could be used:
 
          setlocale(LC_CTYPE, "fr_FR");
@@ -2047,31 +2054,31 @@ LOCALE SUPPORT
          pcre2_set_character_tables(ccontext, tables);
          re = pcre2_compile(..., ccontext);
 
-       The  locale  name "fr_FR" is used on Linux and other Unix-like systems;
+       The locale name "fr_FR" is used on Linux and other  Unix-like  systems;
        if you are using Windows, the name for the French locale is "french".
 
        The pointer that is passed (via the compile context) to pcre2_compile()
        is saved with the compiled pattern, and the same tables are used by the
-       matching functions. Thus,  for  any  single  pattern,  compilation  and
-       matching  both happen in the same locale, but different patterns can be
+       matching  functions.  Thus,  for  any  single  pattern, compilation and
+       matching both happen in the same locale, but different patterns can  be
        processed in different locales.
 
-       It is the caller's responsibility to ensure that the memory  containing
+       It  is the caller's responsibility to ensure that the memory containing
        the tables remains available while they are still in use. When they are
-       no longer needed, you can discard them  using  pcre2_maketables_free(),
-       which  should  pass as its first parameter the same global context that
+       no  longer  needed, you can discard them using pcre2_maketables_free(),
+       which should pass as its first parameter the same global  context  that
        was used to create the tables.
 
    Saving locale tables
 
-       The tables described above are just a sequence of binary  bytes,  which
-       makes  them  independent of hardware characteristics such as endianness
-       or whether the processor is 32-bit or 64-bit. A copy of the  result  of
-       pcre2_maketables()  can  therefore  be saved in a file or elsewhere and
-       re-used later, even in a different program or on another computer.  The
-       size  of  the  tables  (number  of  bytes)  must be obtained by calling
-       pcre2_config()  with  the  PCRE2_CONFIG_TABLES_LENGTH  option   because
-       pcre2_maketables()   does   not   return  this  value.  Note  that  the
+       The  tables  described above are just a sequence of binary bytes, which
+       makes them independent of hardware characteristics such  as  endianness
+       or  whether  the processor is 32-bit or 64-bit. A copy of the result of
+       pcre2_maketables() can therefore be saved in a file  or  elsewhere  and
+       re-used  later, even in a different program or on another computer. The
+       size of the tables (number  of  bytes)  must  be  obtained  by  calling
+       pcre2_config()   with  the  PCRE2_CONFIG_TABLES_LENGTH  option  because
+       pcre2_maketables()  does  not  return  this  value.   Note   that   the
        pcre2_dftables program, which is part of the PCRE2 build system, can be
        used stand-alone to create a file that contains a set of binary tables.
        See the pcre2build documentation for details.
@@ -2081,13 +2088,13 @@ INFORMATION ABOUT A COMPILED PATTERN
 
        int pcre2_pattern_info(const pcre2 *code, uint32_t what, void *where);
 
-       The pcre2_pattern_info() function returns general information  about  a
+       The  pcre2_pattern_info()  function returns general information about a
        compiled pattern. For information about callouts, see the next section.
-       The first argument for pcre2_pattern_info() is a pointer  to  the  com-
+       The  first  argument  for pcre2_pattern_info() is a pointer to the com-
        piled pattern. The second argument specifies which piece of information
-       is required, and the third argument is a pointer to a variable  to  re-
-       ceive  the  data.  If the third argument is NULL, the first argument is
-       ignored, and the function returns the size in  bytes  of  the  variable
+       is  required,  and the third argument is a pointer to a variable to re-
+       ceive the data. If the third argument is NULL, the  first  argument  is
+       ignored,  and  the  function  returns the size in bytes of the variable
        that is required for the information requested. Otherwise, the yield of
        the function is zero for success, or one of the following negative num-
        bers:
@@ -2098,8 +2105,8 @@ INFORMATION ABOUT A COMPILED PATTERN
          PCRE2_ERROR_UNSET          the requested field is not set
 
        The "magic number" is placed at the start of each compiled pattern as a
-       simple check against passing an arbitrary memory  pointer.  Here  is  a
-       typical  call of pcre2_pattern_info(), to obtain the length of the com-
+       simple  check  against  passing  an arbitrary memory pointer. Here is a
+       typical call of pcre2_pattern_info(), to obtain the length of the  com-
        piled pattern:
 
          int rc;
@@ -2117,22 +2124,22 @@ INFORMATION ABOUT A COMPILED PATTERN
          PCRE2_INFO_EXTRAOPTIONS
 
        Return copies of the pattern's options. The third argument should point
-       to a uint32_t variable. PCRE2_INFO_ARGOPTIONS returns exactly  the  op-
-       tions  that  were  passed to pcre2_compile(), whereas PCRE2_INFO_ALLOP-
-       TIONS returns the compile options as modified by any  top-level  (*XXX)
-       option  settings  such  as  (*UTF)  at the start of the pattern itself.
-       PCRE2_INFO_EXTRAOPTIONS returns the extra options that were set in  the
-       compile  context by calling the pcre2_set_compile_extra_options() func-
+       to  a  uint32_t variable. PCRE2_INFO_ARGOPTIONS returns exactly the op-
+       tions that were passed to  pcre2_compile(),  whereas  PCRE2_INFO_ALLOP-
+       TIONS  returns  the compile options as modified by any top-level (*XXX)
+       option settings such as (*UTF) at the  start  of  the  pattern  itself.
+       PCRE2_INFO_EXTRAOPTIONS  returns the extra options that were set in the
+       compile context by calling the pcre2_set_compile_extra_options()  func-
        tion.
 
-       For example, if the pattern /(*UTF)abc/ is compiled with the  PCRE2_EX-
-       TENDED  option,  the result for PCRE2_INFO_ALLOPTIONS is PCRE2_EXTENDED
-       and PCRE2_UTF.  Option settings such as (?i) that can change  within  a
+       For  example, if the pattern /(*UTF)abc/ is compiled with the PCRE2_EX-
+       TENDED option, the result for PCRE2_INFO_ALLOPTIONS  is  PCRE2_EXTENDED
+       and  PCRE2_UTF.   Option settings such as (?i) that can change within a
        pattern do not affect the result of PCRE2_INFO_ALLOPTIONS, even if they
-       appear right at the start of the pattern. (This was different  in  some
+       appear  right  at the start of the pattern. (This was different in some
        earlier releases.)
 
-       A  pattern compiled without PCRE2_ANCHORED is automatically anchored by
+       A pattern compiled without PCRE2_ANCHORED is automatically anchored  by
        PCRE2 if the first significant item in every top-level branch is one of
        the following:
 
@@ -2141,7 +2148,7 @@ INFORMATION ABOUT A COMPILED PATTERN
          \G    always
          .*    sometimes - see below
 
-       When  .* is the first significant item, anchoring is possible only when
+       When .* is the first significant item, anchoring is possible only  when
        all the following are true:
 
          .* is not in an atomic group
@@ -2151,94 +2158,94 @@ INFORMATION ABOUT A COMPILED PATTERN
          Neither (*PRUNE) nor (*SKIP) appears in the pattern
          PCRE2_NO_DOTSTAR_ANCHOR is not set
 
-       For patterns that are auto-anchored, the PCRE2_ANCHORED bit is  set  in
+       For  patterns  that are auto-anchored, the PCRE2_ANCHORED bit is set in
        the options returned for PCRE2_INFO_ALLOPTIONS.
 
          PCRE2_INFO_BACKREFMAX
 
-       Return  the  number  of  the  highest backreference in the pattern. The
-       third argument should point  to  a  uint32_t  variable.  Named  capture
-       groups  acquire  numbers  as well as names, and these count towards the
-       highest backreference. Backreferences such as \4 or  \g{12}  match  the
+       Return the number of the highest  backreference  in  the  pattern.  The
+       third  argument  should  point  to  a  uint32_t variable. Named capture
+       groups acquire numbers as well as names, and these  count  towards  the
+       highest  backreference.  Backreferences  such as \4 or \g{12} match the
        captured characters of the given group, but in addition, the check that
        a capture group is set in a conditional group such as (?(3)a|b) is also
        a backreference.  Zero is returned if there are no backreferences.
 
          PCRE2_INFO_BSR
 
-       The  output  is a uint32_t integer whose value indicates what character
-       sequences the \R escape sequence matches. A value of  PCRE2_BSR_UNICODE
-       means  that  \R  matches  any  Unicode line ending sequence; a value of
+       The output is a uint32_t integer whose value indicates  what  character
+       sequences  the \R escape sequence matches. A value of PCRE2_BSR_UNICODE
+       means that \R matches any Unicode line  ending  sequence;  a  value  of
        PCRE2_BSR_ANYCRLF means that \R matches only CR, LF, or CRLF.
 
          PCRE2_INFO_CAPTURECOUNT
 
-       Return the highest capture group number in  the  pattern.  In  patterns
+       Return  the  highest  capture  group number in the pattern. In patterns
        where (?| is not used, this is also the total number of capture groups.
        The third argument should point to a uint32_t variable.
 
          PCRE2_INFO_DEPTHLIMIT
 
-       If the pattern set a backtracking depth limit by including an  item  of
-       the  form  (*LIMIT_DEPTH=nnnn) at the start, the value is returned. The
+       If  the  pattern set a backtracking depth limit by including an item of
+       the form (*LIMIT_DEPTH=nnnn) at the start, the value is  returned.  The
        third argument should point to a uint32_t integer. If no such value has
-       been  set, the call to pcre2_pattern_info() returns the error PCRE2_ER-
+       been set, the call to pcre2_pattern_info() returns the error  PCRE2_ER-
        ROR_UNSET. Note that this limit will only be used during matching if it
-       is  less  than  the  limit  set or defaulted by the caller of the match
+       is less than the limit set or defaulted by  the  caller  of  the  match
        function.
 
          PCRE2_INFO_FIRSTBITMAP
 
-       In the absence of a single first code unit for a non-anchored  pattern,
-       pcre2_compile()  may construct a 256-bit table that defines a fixed set
-       of values for the first code unit in any match. For example, a  pattern
-       that  starts  with  [abc]  results in a table with three bits set. When
-       code unit values greater than 255 are supported, the flag bit  for  255
-       means  "any  code unit of value 255 or above". If such a table was con-
-       structed, a pointer to it is returned. Otherwise NULL is returned.  The
+       In  the absence of a single first code unit for a non-anchored pattern,
+       pcre2_compile() may construct a 256-bit table that defines a fixed  set
+       of  values for the first code unit in any match. For example, a pattern
+       that starts with [abc] results in a table with  three  bits  set.  When
+       code  unit  values greater than 255 are supported, the flag bit for 255
+       means "any code unit of value 255 or above". If such a table  was  con-
+       structed,  a pointer to it is returned. Otherwise NULL is returned. The
        third argument should point to a const uint8_t * variable.
 
          PCRE2_INFO_FIRSTCODETYPE
 
        Return information about the first code unit of any matched string, for
-       a non-anchored pattern. The third argument should point to  a  uint32_t
-       variable.  If there is a fixed first value, for example, the letter "c"
-       from a pattern such as (cat|cow|coyote), 1 is returned, and  the  value
-       can  be  retrieved using PCRE2_INFO_FIRSTCODEUNIT. If there is no fixed
-       first value, but it is known that a match can occur only at  the  start
-       of  the  subject  or following a newline in the subject, 2 is returned.
+       a  non-anchored  pattern. The third argument should point to a uint32_t
+       variable. If there is a fixed first value, for example, the letter  "c"
+       from  a  pattern such as (cat|cow|coyote), 1 is returned, and the value
+       can be retrieved using PCRE2_INFO_FIRSTCODEUNIT. If there is  no  fixed
+       first  value,  but it is known that a match can occur only at the start
+       of the subject or following a newline in the subject,  2  is  returned.
        Otherwise, and for anchored patterns, 0 is returned.
 
          PCRE2_INFO_FIRSTCODEUNIT
 
-       Return the value of the first code unit of any  matched  string  for  a
-       pattern  where  PCRE2_INFO_FIRSTCODETYPE returns 1; otherwise return 0.
-       The third argument should point to a uint32_t variable.  In  the  8-bit
-       library,  the  value is always less than 256. In the 16-bit library the
-       value can be up to 0xffff. In the 32-bit library  in  UTF-32  mode  the
+       Return  the  value  of  the first code unit of any matched string for a
+       pattern where PCRE2_INFO_FIRSTCODETYPE returns 1; otherwise  return  0.
+       The  third  argument  should point to a uint32_t variable. In the 8-bit
+       library, the value is always less than 256. In the 16-bit  library  the
+       value  can  be  up  to 0xffff. In the 32-bit library in UTF-32 mode the
        value can be up to 0x10ffff, and up to 0xffffffff when not using UTF-32
        mode.
 
          PCRE2_INFO_FRAMESIZE
 
        Return the size (in bytes) of the data frames that are used to remember
-       backtracking  positions  when the pattern is processed by pcre2_match()
-       without the use of JIT. The third argument should  point  to  a  size_t
+       backtracking positions when the pattern is processed  by  pcre2_match()
+       without  the  use  of  JIT. The third argument should point to a size_t
        variable. The frame size depends on the number of capturing parentheses
        in the pattern. Each additional capture group adds two PCRE2_SIZE vari-
        ables.
 
          PCRE2_INFO_HASBACKSLASHC
 
-       Return  1 if the pattern contains any instances of \C, otherwise 0. The
+       Return 1 if the pattern contains any instances of \C, otherwise 0.  The
        third argument should point to a uint32_t variable.
 
          PCRE2_INFO_HASCRORLF
 
-       Return 1 if the pattern contains any explicit  matches  for  CR  or  LF
-       characters,  otherwise 0. The third argument should point to a uint32_t
-       variable. An explicit match is either a literal CR or LF character,  or
-       \r  or  \n  or  one  of  the equivalent hexadecimal or octal escape se-
+       Return  1  if  the  pattern  contains any explicit matches for CR or LF
+       characters, otherwise 0. The third argument should point to a  uint32_t
+       variable.  An explicit match is either a literal CR or LF character, or
+       \r or \n or one of the  equivalent  hexadecimal  or  octal  escape  se-
        quences.
 
          PCRE2_INFO_HEAPLIMIT
@@ -2246,45 +2253,45 @@ INFORMATION ABOUT A COMPILED PATTERN
        If the pattern set a heap memory limit by including an item of the form
        (*LIMIT_HEAP=nnnn) at the start, the value is returned. The third argu-
        ment should point to a uint32_t integer. If no such value has been set,
-       the  call  to pcre2_pattern_info() returns the error PCRE2_ERROR_UNSET.
-       Note that this limit will only be used during matching if  it  is  less
+       the call to pcre2_pattern_info() returns the  error  PCRE2_ERROR_UNSET.
+       Note  that  this  limit will only be used during matching if it is less
        than the limit set or defaulted by the caller of the match function.
 
          PCRE2_INFO_JCHANGED
 
-       Return  1  if  the (?J) or (?-J) option setting is used in the pattern,
-       otherwise 0. The third argument should point to  a  uint32_t  variable.
-       (?J)  and  (?-J) set and unset the local PCRE2_DUPNAMES option, respec-
+       Return 1 if the (?J) or (?-J) option setting is used  in  the  pattern,
+       otherwise  0.  The  third argument should point to a uint32_t variable.
+       (?J) and (?-J) set and unset the local PCRE2_DUPNAMES  option,  respec-
        tively.
 
          PCRE2_INFO_JITSIZE
 
-       If the compiled pattern was successfully  processed  by  pcre2_jit_com-
-       pile(),  return  the  size  of  the JIT compiled code, otherwise return
+       If  the  compiled  pattern was successfully processed by pcre2_jit_com-
+       pile(), return the size of the  JIT  compiled  code,  otherwise  return
        zero. The third argument should point to a size_t variable.
 
          PCRE2_INFO_LASTCODETYPE
 
-       Returns 1 if there is a rightmost literal code unit that must exist  in
-       any  matched string, other than at its start. The third argument should
+       Returns  1 if there is a rightmost literal code unit that must exist in
+       any matched string, other than at its start. The third argument  should
        point to a uint32_t variable. If there is no such value, 0 is returned.
-       When  1  is returned, the code unit value itself can be retrieved using
+       When 1 is returned, the code unit value itself can be  retrieved  using
        PCRE2_INFO_LASTCODEUNIT. For anchored patterns, a last literal value is
-       recorded  only if it follows something of variable length. For example,
-       for the pattern /^a\d+z\d+/ the returned value is 1 (with "z"  returned
-       from  PCRE2_INFO_LASTCODEUNIT), but for /^a\dz\d/ the returned value is
+       recorded only if it follows something of variable length. For  example,
+       for  the pattern /^a\d+z\d+/ the returned value is 1 (with "z" returned
+       from PCRE2_INFO_LASTCODEUNIT), but for /^a\dz\d/ the returned value  is
        0.
 
          PCRE2_INFO_LASTCODEUNIT
 
-       Return the value of the rightmost literal code unit that must exist  in
-       any  matched  string,  other  than  at  its  start, for a pattern where
+       Return  the value of the rightmost literal code unit that must exist in
+       any matched string, other than  at  its  start,  for  a  pattern  where
        PCRE2_INFO_LASTCODETYPE returns 1. Otherwise, return 0. The third argu-
        ment should point to a uint32_t variable.
 
          PCRE2_INFO_MATCHEMPTY
 
-       Return  1  if the pattern might match an empty string, otherwise 0. The
+       Return 1 if the pattern might match an empty string, otherwise  0.  The
        third argument should point to a uint32_t variable. When a pattern con-
        tains recursive subroutine calls it is not always possible to determine
        whether or not it can match an empty string. PCRE2 takes a cautious ap-
@@ -2292,44 +2299,44 @@ INFORMATION ABOUT A COMPILED PATTERN
 
          PCRE2_INFO_MATCHLIMIT
 
-       If  the  pattern  set  a  match  limit by including an item of the form
-       (*LIMIT_MATCH=nnnn) at the start, the value is returned. The third  ar-
-       gument  should  point  to a uint32_t integer. If no such value has been
+       If the pattern set a match limit by  including  an  item  of  the  form
+       (*LIMIT_MATCH=nnnn)  at the start, the value is returned. The third ar-
+       gument should point to a uint32_t integer. If no such  value  has  been
        set, the call to pcre2_pattern_info() returns the error PCRE2_ERROR_UN-
-       SET.  Note  that  this limit will only be used during matching if it is
-       less than the limit set or defaulted by the caller of the  match  func-
+       SET. Note that this limit will only be used during matching  if  it  is
+       less  than  the limit set or defaulted by the caller of the match func-
        tion.
 
          PCRE2_INFO_MAXLOOKBEHIND
 
-       A  lookbehind  assertion moves back a certain number of characters (not
-       code units) when it starts to process each of its  branches.  This  re-
-       quest  returns  the largest of these backward moves. The third argument
+       A lookbehind assertion moves back a certain number of  characters  (not
+       code  units)  when  it starts to process each of its branches. This re-
+       quest returns the largest of these backward moves. The  third  argument
        should point to a uint32_t integer. The simple assertions \b and \B re-
-       quire  a one-character lookbehind and cause PCRE2_INFO_MAXLOOKBEHIND to
-       return 1 in the absence of anything longer. \A also  registers  a  one-
-       character  lookbehind, though it does not actually inspect the previous
+       quire a one-character lookbehind and cause PCRE2_INFO_MAXLOOKBEHIND  to
+       return  1  in  the absence of anything longer. \A also registers a one-
+       character lookbehind, though it does not actually inspect the  previous
        character.
 
        Note that this information is useful for multi-segment matching only if
-       the  pattern  contains  no nested lookbehinds. For example, the pattern
-       (?<=a(?<=ba)c) returns a maximum lookbehind of 2, but when it  is  pro-
-       cessed,  the first lookbehind moves back by two characters, matches one
-       character, then the nested lookbehind also moves back  by  two  charac-
+       the pattern contains no nested lookbehinds. For  example,  the  pattern
+       (?<=a(?<=ba)c)  returns  a maximum lookbehind of 2, but when it is pro-
+       cessed, the first lookbehind moves back by two characters, matches  one
+       character,  then  the  nested lookbehind also moves back by two charac-
        ters. This puts the matching point three characters earlier than it was
-       at the start.  PCRE2_INFO_MAXLOOKBEHIND is really only useful as a  de-
-       bugging  tool.  See  the pcre2partial documentation for a discussion of
+       at  the start.  PCRE2_INFO_MAXLOOKBEHIND is really only useful as a de-
+       bugging tool. See the pcre2partial documentation for  a  discussion  of
        multi-segment matching.
 
          PCRE2_INFO_MINLENGTH
 
-       If a minimum length for matching  subject  strings  was  computed,  its
+       If  a  minimum  length  for  matching subject strings was computed, its
        value is returned. Otherwise the returned value is 0. This value is not
-       computed when PCRE2_NO_START_OPTIMIZE is set. The value is a number  of
-       characters,  which in UTF mode may be different from the number of code
-       units. The third argument should point  to  a  uint32_t  variable.  The
-       value  is a lower bound to the length of any matching string. There may
-       not be any strings of that length that do  actually  match,  but  every
+       computed  when PCRE2_NO_START_OPTIMIZE is set. The value is a number of
+       characters, which in UTF mode may be different from the number of  code
+       units.  The  third  argument  should  point to a uint32_t variable. The
+       value is a lower bound to the length of any matching string. There  may
+       not  be  any  strings  of that length that do actually match, but every
        string that does match is at least that long.
 
          PCRE2_INFO_NAMECOUNT
@@ -2337,51 +2344,51 @@ INFORMATION ABOUT A COMPILED PATTERN
          PCRE2_INFO_NAMETABLE
 
        PCRE2 supports the use of named as well as numbered capturing parenthe-
-       ses. The names are just an additional way of identifying the  parenthe-
+       ses.  The names are just an additional way of identifying the parenthe-
        ses, which still acquire numbers. Several convenience functions such as
-       pcre2_substring_get_byname() are provided for extracting captured  sub-
-       strings  by  name. It is also possible to extract the data directly, by
-       first converting the name to a number in order to  access  the  correct
-       pointers  in the output vector (described with pcre2_match() below). To
+       pcre2_substring_get_byname()  are provided for extracting captured sub-
+       strings by name. It is also possible to extract the data  directly,  by
+       first  converting  the  name to a number in order to access the correct
+       pointers in the output vector (described with pcre2_match() below).  To
        do the conversion, you need to use the name-to-number map, which is de-
        scribed by these three values.
 
-       The  map  consists  of a number of fixed-size entries. PCRE2_INFO_NAME-
-       COUNT gives the number of entries, and  PCRE2_INFO_NAMEENTRYSIZE  gives
-       the  size  of each entry in code units; both of these return a uint32_t
+       The map consists of a number of  fixed-size  entries.  PCRE2_INFO_NAME-
+       COUNT  gives  the number of entries, and PCRE2_INFO_NAMEENTRYSIZE gives
+       the size of each entry in code units; both of these return  a  uint32_t
        value. The entry size depends on the length of the longest name.
 
        PCRE2_INFO_NAMETABLE returns a pointer to the first entry of the table.
        This is a PCRE2_SPTR pointer to a block of code units. In the 8-bit li-
-       brary, the first two bytes of each entry are the number of the  captur-
-       ing  parenthesis,  most  significant byte first. In the 16-bit library,
-       the pointer points to 16-bit code units, the first  of  which  contains
-       the  parenthesis  number.  In the 32-bit library, the pointer points to
-       32-bit code units, the first of which contains the parenthesis  number.
+       brary,  the first two bytes of each entry are the number of the captur-
+       ing parenthesis, most significant byte first. In  the  16-bit  library,
+       the  pointer  points  to 16-bit code units, the first of which contains
+       the parenthesis number. In the 32-bit library, the  pointer  points  to
+       32-bit  code units, the first of which contains the parenthesis number.
        The rest of the entry is the corresponding name, zero terminated.
 
-       The  names are in alphabetical order. If (?| is used to create multiple
+       The names are in alphabetical order. If (?| is used to create  multiple
        capture groups with the same number, as described in the section on du-
        plicate group numbers in the pcre2pattern page, the groups may be given
-       the same name, but there is only one  entry  in  the  table.  Different
+       the  same  name,  but  there  is only one entry in the table. Different
        names for groups of the same number are not permitted.
 
-       Duplicate  names  for capture groups with different numbers are permit-
+       Duplicate names for capture groups with different numbers  are  permit-
        ted, but only if PCRE2_DUPNAMES is set. They appear in the table in the
-       order  in  which  they were found in the pattern. In the absence of (?|
-       this is the order of increasing number; when (?| is used  this  is  not
-       necessarily  the  case because later capture groups may have lower num-
+       order in which they were found in the pattern. In the  absence  of  (?|
+       this  is  the  order of increasing number; when (?| is used this is not
+       necessarily the case because later capture groups may have  lower  num-
        bers.
 
-       As a simple example of the name/number table,  consider  the  following
-       pattern  after  compilation by the 8-bit library (assume PCRE2_EXTENDED
+       As  a  simple  example of the name/number table, consider the following
+       pattern after compilation by the 8-bit library  (assume  PCRE2_EXTENDED
        is set, so white space - including newlines - is ignored):
 
          (? (?(\d\d)?\d\d) -
          (?\d\d) - (?\d\d) )
 
        There are four named capture groups, so the table has four entries, and
-       each  entry  in the table is eight bytes long. The table is as follows,
+       each entry in the table is eight bytes long. The table is  as  follows,
        with non-printing bytes shows in hexadecimal, and undefined bytes shown
        as ??:
 
@@ -2390,8 +2397,8 @@ INFORMATION ABOUT A COMPILED PATTERN
          00 04 m  o  n  t  h  00
          00 02 y  e  a  r  00 ??
 
-       When  writing  code to extract data from named capture groups using the
-       name-to-number map, remember that the length of the entries  is  likely
+       When writing code to extract data from named capture groups  using  the
+       name-to-number  map,  remember that the length of the entries is likely
        to be different for each compiled pattern.
 
          PCRE2_INFO_NEWLINE
@@ -2410,14 +2417,14 @@ INFORMATION ABOUT A COMPILED PATTERN
 
          PCRE2_INFO_SIZE
 
-       Return the size of the compiled pattern in bytes  (for  all  three  li-
-       braries).  The  third  argument should point to a size_t variable. This
-       value includes the size of the general data  block  that  precedes  the
-       code  units of the compiled pattern itself. The value that is used when
-       pcre2_compile() is getting memory in which to place the  compiled  pat-
+       Return  the  size  of  the compiled pattern in bytes (for all three li-
+       braries). The third argument should point to a  size_t  variable.  This
+       value  includes  the  size  of the general data block that precedes the
+       code units of the compiled pattern itself. The value that is used  when
+       pcre2_compile()  is  getting memory in which to place the compiled pat-
        tern may be slightly larger than the value returned by this option, be-
-       cause there are cases where the code that calculates the  size  has  to
-       over-estimate.  Processing a pattern with the JIT compiler does not al-
+       cause  there  are  cases where the code that calculates the size has to
+       over-estimate. Processing a pattern with the JIT compiler does not  al-
        ter the value returned by this option.
 
 
@@ -2428,30 +2435,30 @@ INFORMATION ABOUT A PATTERN'S CALLOUTS
          void *user_data);
 
        A script language that supports the use of string arguments in callouts
-       might  like  to  scan  all the callouts in a pattern before running the
+       might like to scan all the callouts in a  pattern  before  running  the
        match. This can be done by calling pcre2_callout_enumerate(). The first
-       argument  is  a  pointer  to a compiled pattern, the second points to a
-       callback function, and the third is arbitrary user data.  The  callback
-       function  is  called  for  every callout in the pattern in the order in
+       argument is a pointer to a compiled pattern, the  second  points  to  a
+       callback  function,  and the third is arbitrary user data. The callback
+       function is called for every callout in the pattern  in  the  order  in
        which they appear. Its first argument is a pointer to a callout enumer-
-       ation  block,  and  its second argument is the user_data value that was
-       passed to pcre2_callout_enumerate(). The contents of the  callout  enu-
-       meration  block  are described in the pcre2callout documentation, which
+       ation block, and its second argument is the user_data  value  that  was
+       passed  to  pcre2_callout_enumerate(). The contents of the callout enu-
+       meration block are described in the pcre2callout  documentation,  which
        also gives further details about callouts.
 
 
 SERIALIZATION AND PRECOMPILING
 
-       It is possible to save compiled patterns  on  disc  or  elsewhere,  and
-       reload  them  later,  subject  to a number of restrictions. The host on
-       which the patterns are reloaded must be running  the  same  version  of
+       It  is  possible  to  save  compiled patterns on disc or elsewhere, and
+       reload them later, subject to a number of  restrictions.  The  host  on
+       which  the  patterns  are  reloaded must be running the same version of
        PCRE2, with the same code unit width, and must also have the same endi-
-       anness, pointer width, and PCRE2_SIZE type.  Before  compiled  patterns
-       can  be  saved, they must be converted to a "serialized" form, which in
-       the case of PCRE2 is really just a bytecode dump.  The functions  whose
-       names  begin  with pcre2_serialize_ are used for converting to and from
-       the serialized form. They are described in the pcre2serialize  documen-
-       tation.  Note  that  PCRE2 serialization does not convert compiled pat-
+       anness,  pointer  width,  and PCRE2_SIZE type. Before compiled patterns
+       can be saved, they must be converted to a "serialized" form,  which  in
+       the  case of PCRE2 is really just a bytecode dump.  The functions whose
+       names begin with pcre2_serialize_ are used for converting to  and  from
+       the  serialized form. They are described in the pcre2serialize documen-
+       tation. Note that PCRE2 serialization does not  convert  compiled  pat-
        terns to an abstract format like Java or .NET serialization.
 
 
@@ -2465,68 +2472,68 @@ THE MATCH DATA BLOCK
 
        void pcre2_match_data_free(pcre2_match_data *match_data);
 
-       Information about a successful or unsuccessful match  is  placed  in  a
-       match  data  block,  which  is  an opaque structure that is accessed by
-       function calls. In particular, the match data block contains  a  vector
+       Information  about  a  successful  or unsuccessful match is placed in a
+       match data block, which is an opaque  structure  that  is  accessed  by
+       function  calls.  In particular, the match data block contains a vector
        of offsets into the subject string that define the matched parts of the
        subject. This is known as the ovector.
 
-       Before calling pcre2_match(), pcre2_dfa_match(),  or  pcre2_jit_match()
+       Before  calling  pcre2_match(), pcre2_dfa_match(), or pcre2_jit_match()
        you must create a match data block by calling one of the creation func-
-       tions above. For pcre2_match_data_create(), the first argument  is  the
+       tions  above.  For pcre2_match_data_create(), the first argument is the
        number of pairs of offsets in the ovector.
 
-       When  using  pcre2_match(), one pair of offsets is required to identify
-       the string that matched the whole pattern, with an additional pair  for
+       When using pcre2_match(), one pair of offsets is required  to  identify
+       the  string that matched the whole pattern, with an additional pair for
        each captured substring. For example, a value of 4 creates enough space
-       to record the matched portion of the subject plus three  captured  sub-
+       to  record  the matched portion of the subject plus three captured sub-
        strings.
 
-       When  using  pcre2_dfa_match() there may be multiple matched substrings
-       of different lengths at the same point  in  the  subject.  The  ovector
+       When using pcre2_dfa_match() there may be multiple  matched  substrings
+       of  different  lengths  at  the  same point in the subject. The ovector
        should be made large enough to hold as many as are expected.
 
-       A  minimum  of at least 1 pair is imposed by pcre2_match_data_create(),
-       so it is always possible to return the overall matched  string  in  the
-       case   of   pcre2_match()   or   the  longest  match  in  the  case  of
+       A minimum of at least 1 pair is imposed  by  pcre2_match_data_create(),
+       so  it  is  always possible to return the overall matched string in the
+       case  of  pcre2_match()  or  the  longest  match   in   the   case   of
        pcre2_dfa_match().
 
        The second argument of pcre2_match_data_create() is a pointer to a gen-
-       eral  context, which can specify custom memory management for obtaining
+       eral context, which can specify custom memory management for  obtaining
        the memory for the match data block. If you are not using custom memory
        management, pass NULL, which causes malloc() to be used.
 
-       For  pcre2_match_data_create_from_pattern(),  the  first  argument is a
+       For pcre2_match_data_create_from_pattern(), the  first  argument  is  a
        pointer to a compiled pattern. The ovector is created to be exactly the
-       right  size  to  hold  all  the substrings a pattern might capture when
+       right size to hold all the substrings  a  pattern  might  capture  when
        matched using pcre2_match(). You should not use this call when matching
-       with  pcre2_dfa_match().  The  second  argument is again a pointer to a
-       general context, but in this case if NULL is passed, the memory is  ob-
-       tained  using the same allocator that was used for the compiled pattern
+       with pcre2_dfa_match(). The second argument is again  a  pointer  to  a
+       general  context, but in this case if NULL is passed, the memory is ob-
+       tained using the same allocator that was used for the compiled  pattern
        (custom or default).
 
-       A match data block can be used many times, with the same  or  different
-       compiled  patterns. You can extract information from a match data block
-       after a match operation has finished,  using  functions  that  are  de-
+       A  match  data block can be used many times, with the same or different
+       compiled patterns. You can extract information from a match data  block
+       after  a  match  operation  has  finished, using functions that are de-
        scribed in the sections on matched strings and other match data below.
 
-       When  a  call  of  pcre2_match()  fails, valid data is available in the
-       match block only  when  the  error  is  PCRE2_ERROR_NOMATCH,  PCRE2_ER-
-       ROR_PARTIAL,  or  one of the error codes for an invalid UTF string. Ex-
+       When a call of pcre2_match() fails, valid  data  is  available  in  the
+       match  block  only  when  the  error  is PCRE2_ERROR_NOMATCH, PCRE2_ER-
+       ROR_PARTIAL, or one of the error codes for an invalid UTF  string.  Ex-
        actly what is available depends on the error, and is detailed below.
 
-       When one of the matching functions is called, pointers to the  compiled
-       pattern  and the subject string are set in the match data block so that
-       they can be referenced by the extraction functions after  a  successful
+       When  one of the matching functions is called, pointers to the compiled
+       pattern and the subject string are set in the match data block so  that
+       they  can  be referenced by the extraction functions after a successful
        match. After running a match, you must not free a compiled pattern or a
-       subject string until after all operations on the match data block  (for
-       that  match)  have  taken  place,  unless,  in  the case of the subject
-       string, you have used the PCRE2_COPY_MATCHED_SUBJECT option,  which  is
-       described  in  the section entitled "Option bits for pcre2_match()" be-
+       subject  string until after all operations on the match data block (for
+       that match) have taken place,  unless,  in  the  case  of  the  subject
+       string,  you  have used the PCRE2_COPY_MATCHED_SUBJECT option, which is
+       described in the section entitled "Option bits for  pcre2_match()"  be-
        low.
 
-       When a match data block itself is no longer needed, it should be  freed
-       by  calling  pcre2_match_data_free(). If this function is called with a
+       When  a match data block itself is no longer needed, it should be freed
+       by calling pcre2_match_data_free(). If this function is called  with  a
        NULL argument, it returns immediately, without doing anything.
 
 
@@ -2537,15 +2544,15 @@ MATCHING A PATTERN: THE TRADITIONAL FUNCTION
          uint32_t options, pcre2_match_data *match_data,
          pcre2_match_context *mcontext);
 
-       The function pcre2_match() is called to match a subject string  against
-       a  compiled pattern, which is passed in the code argument. You can call
+       The  function pcre2_match() is called to match a subject string against
+       a compiled pattern, which is passed in the code argument. You can  call
        pcre2_match() with the same code argument as many times as you like, in
-       order  to  find multiple matches in the subject string or to match dif-
+       order to find multiple matches in the subject string or to  match  dif-
        ferent subject strings with the same pattern.
 
-       This function is the main matching facility of the library, and it  op-
-       erates  in  a Perl-like manner. For specialist use there is also an al-
-       ternative matching function, which is described below  in  the  section
+       This  function is the main matching facility of the library, and it op-
+       erates in a Perl-like manner. For specialist use there is also  an  al-
+       ternative  matching  function,  which is described below in the section
        about the pcre2_dfa_match() function.
 
        Here is an example of a simple call to pcre2_match():
@@ -2560,215 +2567,215 @@ MATCHING A PATTERN: THE TRADITIONAL FUNCTION
            md,             /* the match data block */
            NULL);          /* a match context; NULL means use defaults */
 
-       If  the  subject  string is zero-terminated, the length can be given as
+       If the subject string is zero-terminated, the length can  be  given  as
        PCRE2_ZERO_TERMINATED. A match context must be provided if certain less
        common matching parameters are to be changed. For details, see the sec-
        tion on the match context above.
 
    The string to be matched by pcre2_match()
 
-       The subject string is passed to pcre2_match() as a pointer in  subject,
-       a  length  in  length, and a starting offset in startoffset. The length
-       and offset are in code units, not characters.  That  is,  they  are  in
-       bytes  for the 8-bit library, 16-bit code units for the 16-bit library,
-       and 32-bit code units for the 32-bit library, whether or not  UTF  pro-
+       The  subject string is passed to pcre2_match() as a pointer in subject,
+       a length in length, and a starting offset in  startoffset.  The  length
+       and  offset  are  in  code units, not characters.  That is, they are in
+       bytes for the 8-bit library, 16-bit code units for the 16-bit  library,
+       and  32-bit  code units for the 32-bit library, whether or not UTF pro-
        cessing is enabled.
 
        If startoffset is greater than the length of the subject, pcre2_match()
-       returns PCRE2_ERROR_BADOFFSET. When the starting offset  is  zero,  the
-       search  for a match starts at the beginning of the subject, and this is
+       returns  PCRE2_ERROR_BADOFFSET.  When  the starting offset is zero, the
+       search for a match starts at the beginning of the subject, and this  is
        by far the most common case. In UTF-8 or UTF-16 mode, the starting off-
-       set  must  point to the start of a character, or to the end of the sub-
-       ject (in UTF-32 mode, one code unit equals one character, so  all  off-
-       sets  are  valid). Like the pattern string, the subject may contain bi-
+       set must point to the start of a character, or to the end of  the  sub-
+       ject  (in  UTF-32 mode, one code unit equals one character, so all off-
+       sets are valid). Like the pattern string, the subject may  contain  bi-
        nary zeros.
 
-       A non-zero starting offset is useful when searching for  another  match
-       in  the  same  subject  by calling pcre2_match() again after a previous
-       success.  Setting startoffset differs from  passing  over  a  shortened
-       string  and  setting  PCRE2_NOTBOL in the case of a pattern that begins
+       A  non-zero  starting offset is useful when searching for another match
+       in the same subject by calling pcre2_match()  again  after  a  previous
+       success.   Setting  startoffset  differs  from passing over a shortened
+       string and setting PCRE2_NOTBOL in the case of a  pattern  that  begins
        with any kind of lookbehind. For example, consider the pattern
 
          \Biss\B
 
-       which finds occurrences of "iss" in the middle of  words.  (\B  matches
-       only  if  the  current position in the subject is not a word boundary.)
-       When  applied  to  the  string  "Mississippi"   the   first   call   to
-       pcre2_match()  finds  the  first occurrence. If pcre2_match() is called
+       which  finds  occurrences  of "iss" in the middle of words. (\B matches
+       only if the current position in the subject is not  a  word  boundary.)
+       When   applied   to   the   string  "Mississippi"  the  first  call  to
+       pcre2_match() finds the first occurrence. If  pcre2_match()  is  called
        again with just the remainder of the subject, namely "issippi", it does
-       not  match,  because  \B  is  always false at the start of the subject,
-       which is deemed to be a word boundary.  However,  if  pcre2_match()  is
+       not match, because \B is always false at  the  start  of  the  subject,
+       which  is  deemed  to  be a word boundary. However, if pcre2_match() is
        passed the entire string again, but with startoffset set to 4, it finds
-       the second occurrence of "iss" because it is able to  look  behind  the
+       the  second  occurrence  of "iss" because it is able to look behind the
        starting point to discover that it is preceded by a letter.
 
-       Finding  all  the  matches  in a subject is tricky when the pattern can
+       Finding all the matches in a subject is tricky  when  the  pattern  can
        match an empty string. It is possible to emulate Perl's /g behaviour by
-       first   trying   the   match   again  at  the  same  offset,  with  the
-       PCRE2_NOTEMPTY_ATSTART and PCRE2_ANCHORED options,  and  then  if  that
-       fails,  advancing  the  starting  offset  and  trying an ordinary match
-       again. There is some code that demonstrates  how  to  do  this  in  the
-       pcre2demo  sample  program. In the most general case, you have to check
-       to see if the newline convention recognizes CRLF as a newline,  and  if
-       so,  and the current character is CR followed by LF, advance the start-
+       first  trying  the  match  again  at  the   same   offset,   with   the
+       PCRE2_NOTEMPTY_ATSTART  and  PCRE2_ANCHORED  options,  and then if that
+       fails, advancing the starting  offset  and  trying  an  ordinary  match
+       again.  There  is  some  code  that  demonstrates how to do this in the
+       pcre2demo sample program. In the most general case, you have  to  check
+       to  see  if the newline convention recognizes CRLF as a newline, and if
+       so, and the current character is CR followed by LF, advance the  start-
        ing offset by two characters instead of one.
 
        If a non-zero starting offset is passed when the pattern is anchored, a
        single attempt to match at the given offset is made. This can only suc-
-       ceed if the pattern does not require the match to be at  the  start  of
-       the  subject.  In other words, the anchoring must be the result of set-
-       ting the PCRE2_ANCHORED option or the use of .* with PCRE2_DOTALL,  not
+       ceed  if  the  pattern does not require the match to be at the start of
+       the subject. In other words, the anchoring must be the result  of  set-
+       ting  the PCRE2_ANCHORED option or the use of .* with PCRE2_DOTALL, not
        by starting the pattern with ^ or \A.
 
    Option bits for pcre2_match()
 
        The unused bits of the options argument for pcre2_match() must be zero.
-       The   only   bits    that    may    be    set    are    PCRE2_ANCHORED,
-       PCRE2_COPY_MATCHED_SUBJECT,  PCRE2_ENDANCHORED, PCRE2_NOTBOL, PCRE2_NO-
+       The    only    bits    that    may    be    set   are   PCRE2_ANCHORED,
+       PCRE2_COPY_MATCHED_SUBJECT, PCRE2_ENDANCHORED, PCRE2_NOTBOL,  PCRE2_NO-
        TEOL,     PCRE2_NOTEMPTY,     PCRE2_NOTEMPTY_ATSTART,     PCRE2_NO_JIT,
-       PCRE2_NO_UTF_CHECK,  PCRE2_PARTIAL_HARD,  and PCRE2_PARTIAL_SOFT. Their
+       PCRE2_NO_UTF_CHECK, PCRE2_PARTIAL_HARD, and  PCRE2_PARTIAL_SOFT.  Their
        action is described below.
 
-       Setting PCRE2_ANCHORED or PCRE2_ENDANCHORED at match time is  not  sup-
-       ported  by  the just-in-time (JIT) compiler. If it is set, JIT matching
-       is disabled and the interpretive code in pcre2_match()  is  run.  Apart
-       from  PCRE2_NO_JIT (obviously), the remaining options are supported for
+       Setting  PCRE2_ANCHORED  or PCRE2_ENDANCHORED at match time is not sup-
+       ported by the just-in-time (JIT) compiler. If it is set,  JIT  matching
+       is  disabled  and  the interpretive code in pcre2_match() is run. Apart
+       from PCRE2_NO_JIT (obviously), the remaining options are supported  for
        JIT matching.
 
          PCRE2_ANCHORED
 
        The PCRE2_ANCHORED option limits pcre2_match() to matching at the first
-       matching  position.  If  a pattern was compiled with PCRE2_ANCHORED, or
-       turned out to be anchored by virtue of its contents, it cannot be  made
-       unachored  at matching time. Note that setting the option at match time
+       matching position. If a pattern was compiled  with  PCRE2_ANCHORED,  or
+       turned  out to be anchored by virtue of its contents, it cannot be made
+       unachored at matching time. Note that setting the option at match  time
        disables JIT matching.
 
          PCRE2_COPY_MATCHED_SUBJECT
 
-       By default, a pointer to the subject is remembered in  the  match  data
-       block  so  that,  after a successful match, it can be referenced by the
-       substring extraction functions. This means that  the  subject's  memory
-       must  not be freed until all such operations are complete. For some ap-
-       plications where the lifetime of the subject string is not  guaranteed,
-       it  may  be  necessary  to make a copy of the subject string, but it is
-       wasteful to do this unless the match is successful. After a  successful
-       match,  if PCRE2_COPY_MATCHED_SUBJECT is set, the subject is copied and
-       the new pointer is remembered in the match data block  instead  of  the
-       original  subject  pointer.  The memory allocator that was used for the
-       match block itself is  used.  The  copy  is  automatically  freed  when
-       pcre2_match_data_free()  is  called to free the match data block. It is
+       By  default,  a  pointer to the subject is remembered in the match data
+       block so that, after a successful match, it can be  referenced  by  the
+       substring  extraction  functions.  This means that the subject's memory
+       must not be freed until all such operations are complete. For some  ap-
+       plications  where the lifetime of the subject string is not guaranteed,
+       it may be necessary to make a copy of the subject  string,  but  it  is
+       wasteful  to do this unless the match is successful. After a successful
+       match, if PCRE2_COPY_MATCHED_SUBJECT is set, the subject is copied  and
+       the  new  pointer  is remembered in the match data block instead of the
+       original subject pointer. The memory allocator that was  used  for  the
+       match  block  itself  is  used.  The  copy  is automatically freed when
+       pcre2_match_data_free() is called to free the match data block.  It  is
        also automatically freed if the match data block is re-used for another
        match operation.
 
          PCRE2_ENDANCHORED
 
-       If  the  PCRE2_ENDANCHORED option is set, any string that pcre2_match()
-       matches must be right at the end of the subject string. Note that  set-
+       If the PCRE2_ENDANCHORED option is set, any string  that  pcre2_match()
+       matches  must be right at the end of the subject string. Note that set-
        ting the option at match time disables JIT matching.
 
          PCRE2_NOTBOL
 
        This option specifies that first character of the subject string is not
-       the beginning of a line, so the  circumflex  metacharacter  should  not
-       match  before  it.  Setting  this without having set PCRE2_MULTILINE at
+       the  beginning  of  a  line, so the circumflex metacharacter should not
+       match before it. Setting this without  having  set  PCRE2_MULTILINE  at
        compile time causes circumflex never to match. This option affects only
        the behaviour of the circumflex metacharacter. It does not affect \A.
 
          PCRE2_NOTEOL
 
        This option specifies that the end of the subject string is not the end
-       of a line, so the dollar metacharacter should not match it nor  (except
-       in  multiline mode) a newline immediately before it. Setting this with-
-       out having set PCRE2_MULTILINE at compile time causes dollar  never  to
+       of  a line, so the dollar metacharacter should not match it nor (except
+       in multiline mode) a newline immediately before it. Setting this  with-
+       out  having  set PCRE2_MULTILINE at compile time causes dollar never to
        match. This option affects only the behaviour of the dollar metacharac-
        ter. It does not affect \Z or \z.
 
          PCRE2_NOTEMPTY
 
        An empty string is not considered to be a valid match if this option is
-       set.  If  there are alternatives in the pattern, they are tried. If all
-       the alternatives match the empty string, the entire  match  fails.  For
+       set. If there are alternatives in the pattern, they are tried.  If  all
+       the  alternatives  match  the empty string, the entire match fails. For
        example, if the pattern
 
          a?b?
 
-       is  applied  to  a  string not beginning with "a" or "b", it matches an
+       is applied to a string not beginning with "a" or  "b",  it  matches  an
        empty string at the start of the subject. With PCRE2_NOTEMPTY set, this
-       match  is  not valid, so pcre2_match() searches further into the string
+       match is not valid, so pcre2_match() searches further into  the  string
        for occurrences of "a" or "b".
 
          PCRE2_NOTEMPTY_ATSTART
 
-       This is like PCRE2_NOTEMPTY, except that it locks out an  empty  string
+       This  is  like PCRE2_NOTEMPTY, except that it locks out an empty string
        match only at the first matching position, that is, at the start of the
-       subject plus the starting offset. An empty string match  later  in  the
+       subject  plus  the  starting offset. An empty string match later in the
        subject is permitted.  If the pattern is anchored, such a match can oc-
        cur only if the pattern contains \K.
 
          PCRE2_NO_JIT
 
-       By  default,  if  a  pattern  has  been   successfully   processed   by
-       pcre2_jit_compile(),  JIT  is  automatically used when pcre2_match() is
-       called with options that JIT supports.  Setting  PCRE2_NO_JIT  disables
+       By   default,   if   a  pattern  has  been  successfully  processed  by
+       pcre2_jit_compile(), JIT is automatically used  when  pcre2_match()  is
+       called  with  options  that JIT supports. Setting PCRE2_NO_JIT disables
        the use of JIT; it forces matching to be done by the interpreter.
 
          PCRE2_NO_UTF_CHECK
 
        When PCRE2_UTF is set at compile time, the validity of the subject as a
-       UTF  string  is  checked  unless  PCRE2_NO_UTF_CHECK   is   passed   to
+       UTF   string   is   checked  unless  PCRE2_NO_UTF_CHECK  is  passed  to
        pcre2_match() or PCRE2_MATCH_INVALID_UTF was passed to pcre2_compile().
        The latter special case is discussed in detail in the pcre2unicode doc-
        umentation.
 
-       In  the default case, if a non-zero starting offset is given, the check
-       is applied only to that part of the subject  that  could  be  inspected
-       during  matching,  and there is a check that the starting offset points
-       to the first code unit of a character or to the end of the subject.  If
-       there  are no lookbehind assertions in the pattern, the check starts at
+       In the default case, if a non-zero starting offset is given, the  check
+       is  applied  only  to  that part of the subject that could be inspected
+       during matching, and there is a check that the starting  offset  points
+       to  the first code unit of a character or to the end of the subject. If
+       there are no lookbehind assertions in the pattern, the check starts  at
        the starting offset.  Otherwise, it starts at the length of the longest
-       lookbehind  before  the starting offset, or at the start of the subject
-       if there are not that many characters before the starting offset.  Note
+       lookbehind before the starting offset, or at the start of  the  subject
+       if  there are not that many characters before the starting offset. Note
        that the sequences \b and \B are one-character lookbehinds.
 
        The check is carried out before any other processing takes place, and a
-       negative error code is returned if the check fails. There  are  several
-       UTF  error  codes  for each code unit width, corresponding to different
-       problems with the code unit sequence. There are discussions  about  the
-       validity  of  UTF-8  strings, UTF-16 strings, and UTF-32 strings in the
+       negative  error  code is returned if the check fails. There are several
+       UTF error codes for each code unit width,  corresponding  to  different
+       problems  with  the code unit sequence. There are discussions about the
+       validity of UTF-8 strings, UTF-16 strings, and UTF-32  strings  in  the
        pcre2unicode documentation.
 
        If you know that your subject is valid, and you want to skip this check
        for performance reasons, you can set the PCRE2_NO_UTF_CHECK option when
-       calling pcre2_match(). You might want to do this  for  the  second  and
-       subsequent  calls  to pcre2_match() if you are making repeated calls to
+       calling  pcre2_match().  You  might  want to do this for the second and
+       subsequent calls to pcre2_match() if you are making repeated  calls  to
        find multiple matches in the same subject string.
 
-       Warning: Unless PCRE2_MATCH_INVALID_UTF was set at compile  time,  when
-       PCRE2_NO_UTF_CHECK  is  set  at match time the effect of passing an in-
+       Warning:  Unless  PCRE2_MATCH_INVALID_UTF was set at compile time, when
+       PCRE2_NO_UTF_CHECK is set at match time the effect of  passing  an  in-
        valid string as a subject, or an invalid value of startoffset, is unde-
-       fined.   Your  program may crash or loop indefinitely or give wrong re-
+       fined.  Your program may crash or loop indefinitely or give  wrong  re-
        sults.
 
          PCRE2_PARTIAL_HARD
          PCRE2_PARTIAL_SOFT
 
        These options turn on the partial matching feature. A partial match oc-
-       curs  if  the  end  of  the subject string is reached successfully, but
+       curs if the end of the subject  string  is  reached  successfully,  but
        there are not enough subject characters to complete the match. In addi-
-       tion,  either  at  least  one character must have been inspected or the
-       pattern must contain a lookbehind, or the  pattern  must  be  one  that
+       tion, either at least one character must have  been  inspected  or  the
+       pattern  must  contain  a  lookbehind,  or the pattern must be one that
        could match an empty string.
 
-       If  this  situation  arises when PCRE2_PARTIAL_SOFT (but not PCRE2_PAR-
+       If this situation arises when PCRE2_PARTIAL_SOFT  (but  not  PCRE2_PAR-
        TIAL_HARD) is set, matching continues by testing any remaining alterna-
-       tives.  Only  if  no complete match can be found is PCRE2_ERROR_PARTIAL
-       returned instead of PCRE2_ERROR_NOMATCH.  In  other  words,  PCRE2_PAR-
-       TIAL_SOFT  specifies  that  the  caller is prepared to handle a partial
+       tives. Only if no complete match can be  found  is  PCRE2_ERROR_PARTIAL
+       returned  instead  of  PCRE2_ERROR_NOMATCH.  In other words, PCRE2_PAR-
+       TIAL_SOFT specifies that the caller is prepared  to  handle  a  partial
        match, but only if no complete match can be found.
 
-       If PCRE2_PARTIAL_HARD is set, it overrides PCRE2_PARTIAL_SOFT. In  this
-       case,  if  a  partial match is found, pcre2_match() immediately returns
-       PCRE2_ERROR_PARTIAL, without considering  any  other  alternatives.  In
+       If  PCRE2_PARTIAL_HARD is set, it overrides PCRE2_PARTIAL_SOFT. In this
+       case, if a partial match is found,  pcre2_match()  immediately  returns
+       PCRE2_ERROR_PARTIAL,  without  considering  any  other alternatives. In
        other words, when PCRE2_PARTIAL_HARD is set, a partial match is consid-
        ered to be more important that an alternative complete match.
 
@@ -2778,38 +2785,38 @@ MATCHING A PATTERN: THE TRADITIONAL FUNCTION
 
 NEWLINE HANDLING WHEN MATCHING
 
-       When  PCRE2 is built, a default newline convention is set; this is usu-
-       ally the standard convention for the operating system. The default  can
-       be  overridden  in a compile context by calling pcre2_set_newline(). It
-       can also be overridden by starting a pattern string with, for  example,
-       (*CRLF),  as  described  in  the  section on newline conventions in the
-       pcre2pattern page. During matching, the newline choice affects the  be-
-       haviour  of the dot, circumflex, and dollar metacharacters. It may also
-       alter the way the match starting position is  advanced  after  a  match
+       When PCRE2 is built, a default newline convention is set; this is  usu-
+       ally  the standard convention for the operating system. The default can
+       be overridden in a compile context by calling  pcre2_set_newline().  It
+       can  also be overridden by starting a pattern string with, for example,
+       (*CRLF), as described in the section  on  newline  conventions  in  the
+       pcre2pattern  page. During matching, the newline choice affects the be-
+       haviour of the dot, circumflex, and dollar metacharacters. It may  also
+       alter  the  way  the  match starting position is advanced after a match
        failure for an unanchored pattern.
 
        When PCRE2_NEWLINE_CRLF, PCRE2_NEWLINE_ANYCRLF, or PCRE2_NEWLINE_ANY is
-       set as the newline convention, and a match attempt  for  an  unanchored
+       set  as  the  newline convention, and a match attempt for an unanchored
        pattern fails when the current starting position is at a CRLF sequence,
-       and the pattern contains no explicit matches for CR or  LF  characters,
-       the  match  position  is  advanced by two characters instead of one, in
+       and  the  pattern contains no explicit matches for CR or LF characters,
+       the match position is advanced by two characters  instead  of  one,  in
        other words, to after the CRLF.
 
        The above rule is a compromise that makes the most common cases work as
-       expected.  For example, if the pattern is .+A (and the PCRE2_DOTALL op-
-       tion is not set), it does not match the string "\r\nA"  because,  after
-       failing  at the start, it skips both the CR and the LF before retrying.
-       However, the pattern [\r\n]A does match that string,  because  it  con-
+       expected. For example, if the pattern is .+A (and the PCRE2_DOTALL  op-
+       tion  is  not set), it does not match the string "\r\nA" because, after
+       failing at the start, it skips both the CR and the LF before  retrying.
+       However,  the  pattern  [\r\n]A does match that string, because it con-
        tains an explicit CR or LF reference, and so advances only by one char-
        acter after the first failure.
 
        An explicit match for CR of LF is either a literal appearance of one of
-       those  characters  in the pattern, or one of the \r or \n or equivalent
+       those characters in the pattern, or one of the \r or \n  or  equivalent
        octal or hexadecimal escape sequences. Implicit matches such as [^X] do
-       not  count, nor does \s, even though it includes CR and LF in the char-
+       not count, nor does \s, even though it includes CR and LF in the  char-
        acters that it matches.
 
-       Notwithstanding the above, anomalous effects may still occur when  CRLF
+       Notwithstanding  the above, anomalous effects may still occur when CRLF
        is a valid newline sequence and explicit \r or \n escapes appear in the
        pattern.
 
@@ -2820,82 +2827,82 @@ HOW PCRE2_MATCH() RETURNS A STRING AND CAPTURED SUBSTRINGS
 
        PCRE2_SIZE *pcre2_get_ovector_pointer(pcre2_match_data *match_data);
 
-       In general, a pattern matches a certain portion of the subject, and  in
-       addition,  further  substrings  from  the  subject may be picked out by
-       parenthesized parts of the pattern.  Following  the  usage  in  Jeffrey
-       Friedl's  book,  this  is  called  "capturing" in what follows, and the
-       phrase "capture group" (Perl terminology) is used for a fragment  of  a
-       pattern  that picks out a substring. PCRE2 supports several other kinds
+       In  general, a pattern matches a certain portion of the subject, and in
+       addition, further substrings from the subject  may  be  picked  out  by
+       parenthesized  parts  of  the  pattern.  Following the usage in Jeffrey
+       Friedl's book, this is called "capturing"  in  what  follows,  and  the
+       phrase  "capture  group" (Perl terminology) is used for a fragment of a
+       pattern that picks out a substring. PCRE2 supports several other  kinds
        of parenthesized group that do not cause substrings to be captured. The
-       pcre2_pattern_info()  function can be used to find out how many capture
+       pcre2_pattern_info() function can be used to find out how many  capture
        groups there are in a compiled pattern.
 
-       You can use auxiliary functions for accessing  captured  substrings  by
+       You  can  use  auxiliary functions for accessing captured substrings by
        number or by name, as described in sections below.
 
        Alternatively, you can make direct use of the vector of PCRE2_SIZE val-
-       ues, called  the  ovector,  which  contains  the  offsets  of  captured
-       strings.   It   is   part  of  the  match  data  block.   The  function
-       pcre2_get_ovector_pointer() returns the address  of  the  ovector,  and
+       ues,  called  the  ovector,  which  contains  the  offsets  of captured
+       strings.  It  is  part  of  the  match  data   block.    The   function
+       pcre2_get_ovector_pointer()  returns  the  address  of the ovector, and
        pcre2_get_ovector_count() returns the number of pairs of values it con-
        tains.
 
        Within the ovector, the first in each pair of values is set to the off-
        set of the first code unit of a substring, and the second is set to the
-       offset of the first code unit after the end of a substring. These  val-
-       ues  are always code unit offsets, not character offsets. That is, they
+       offset  of the first code unit after the end of a substring. These val-
+       ues are always code unit offsets, not character offsets. That is,  they
        are byte offsets in the 8-bit library, 16-bit offsets in the 16-bit li-
        brary, and 32-bit offsets in the 32-bit library.
 
-       After  a  partial  match  (error  return PCRE2_ERROR_PARTIAL), only the
-       first pair of offsets (that is, ovector[0]  and  ovector[1])  are  set.
-       They  identify  the part of the subject that was partially matched. See
+       After a partial match  (error  return  PCRE2_ERROR_PARTIAL),  only  the
+       first  pair  of  offsets  (that is, ovector[0] and ovector[1]) are set.
+       They identify the part of the subject that was partially  matched.  See
        the pcre2partial documentation for details of partial matching.
 
-       After a fully successful match, the first pair  of  offsets  identifies
-       the  portion  of the subject string that was matched by the entire pat-
-       tern. The next pair is used for the first captured  substring,  and  so
-       on.  The  value  returned by pcre2_match() is one more than the highest
-       numbered pair that has been set. For example, if  two  substrings  have
-       been  captured,  the returned value is 3. If there are no captured sub-
+       After  a  fully  successful match, the first pair of offsets identifies
+       the portion of the subject string that was matched by the  entire  pat-
+       tern.  The  next  pair is used for the first captured substring, and so
+       on. The value returned by pcre2_match() is one more  than  the  highest
+       numbered  pair  that  has been set. For example, if two substrings have
+       been captured, the returned value is 3. If there are no  captured  sub-
        strings, the return value from a successful match is 1, indicating that
        just the first pair of offsets has been set.
 
-       If  a  pattern uses the \K escape sequence within a positive assertion,
+       If a pattern uses the \K escape sequence within a  positive  assertion,
        the reported start of a successful match can be greater than the end of
-       the  match.   For  example,  if the pattern (?=ab\K) is matched against
+       the match.  For example, if the pattern  (?=ab\K)  is  matched  against
        "ab", the start and end offset values for the match are 2 and 0.
 
-       If a capture group is matched repeatedly within a single  match  opera-
+       If  a  capture group is matched repeatedly within a single match opera-
        tion, it is the last portion of the subject that it matched that is re-
        turned.
 
        If the ovector is too small to hold all the captured substring offsets,
-       as  much  as possible is filled in, and the function returns a value of
-       zero. If captured substrings are not of interest, pcre2_match() may  be
+       as much as possible is filled in, and the function returns a  value  of
+       zero.  If captured substrings are not of interest, pcre2_match() may be
        called with a match data block whose ovector is of minimum length (that
        is, one pair).
 
-       It is possible for capture group number n+1 to match some part  of  the
-       subject  when  group  n  has  not been used at all. For example, if the
+       It  is  possible for capture group number n+1 to match some part of the
+       subject when group n has not been used at  all.  For  example,  if  the
        string "abc" is matched against the pattern (a|(z))(bc) the return from
-       the  function  is 4, and groups 1 and 3 are matched, but 2 is not. When
-       this happens, both values in the offset pairs corresponding  to  unused
+       the function is 4, and groups 1 and 3 are matched, but 2 is  not.  When
+       this  happens,  both values in the offset pairs corresponding to unused
        groups are set to PCRE2_UNSET.
 
-       Offset  values  that  correspond to unused groups at the end of the ex-
-       pression are also set to PCRE2_UNSET. For example, if the string  "abc"
-       is  matched  against  the pattern (abc)(x(yz)?)? groups 2 and 3 are not
-       matched. The return from the function is 2, because  the  highest  used
-       capture  group  number  is  1. The offsets for for the second and third
-       capture groupss (assuming the vector is large enough,  of  course)  are
+       Offset values that correspond to unused groups at the end  of  the  ex-
+       pression  are also set to PCRE2_UNSET. For example, if the string "abc"
+       is matched against the pattern (abc)(x(yz)?)? groups 2 and  3  are  not
+       matched.  The  return  from the function is 2, because the highest used
+       capture group number is 1. The offsets for for  the  second  and  third
+       capture  groupss  (assuming  the vector is large enough, of course) are
        set to PCRE2_UNSET.
 
        Elements in the ovector that do not correspond to capturing parentheses
        in the pattern are never changed. That is, if a pattern contains n cap-
        turing parentheses, no more than ovector[0] to ovector[2n+1] are set by
-       pcre2_match(). The other elements retain whatever  values  they  previ-
-       ously  had.  After  a failed match attempt, the contents of the ovector
+       pcre2_match().  The  other  elements retain whatever values they previ-
+       ously had. After a failed match attempt, the contents  of  the  ovector
        are unchanged.
 
 
@@ -2905,69 +2912,69 @@ OTHER INFORMATION ABOUT A MATCH
 
        PCRE2_SIZE pcre2_get_startchar(pcre2_match_data *match_data);
 
-       As well as the offsets in the ovector, other information about a  match
-       is  retained  in the match data block and can be retrieved by the above
-       functions in appropriate circumstances. If they  are  called  at  other
+       As  well as the offsets in the ovector, other information about a match
+       is retained in the match data block and can be retrieved by  the  above
+       functions  in  appropriate  circumstances.  If they are called at other
        times, the result is undefined.
 
-       After  a  successful match, a partial match (PCRE2_ERROR_PARTIAL), or a
-       failure to match (PCRE2_ERROR_NOMATCH), a mark name may  be  available.
-       The  function pcre2_get_mark() can be called to access this name, which
-       can be specified in the pattern by  any  of  the  backtracking  control
+       After a successful match, a partial match (PCRE2_ERROR_PARTIAL),  or  a
+       failure  to  match (PCRE2_ERROR_NOMATCH), a mark name may be available.
+       The function pcre2_get_mark() can be called to access this name,  which
+       can  be  specified  in  the  pattern by any of the backtracking control
        verbs, not just (*MARK). The same function applies to all the verbs. It
        returns a pointer to the zero-terminated name, which is within the com-
        piled pattern. If no name is available, NULL is returned. The length of
-       the name (excluding the terminating zero) is stored in  the  code  unit
-       that  precedes  the name. You should use this length instead of relying
+       the  name  (excluding  the terminating zero) is stored in the code unit
+       that precedes the name. You should use this length instead  of  relying
        on the terminating zero if the name might contain a binary zero.
 
-       After a successful match, the name that is returned is  the  last  mark
+       After  a  successful  match, the name that is returned is the last mark
        name encountered on the matching path through the pattern. Instances of
-       backtracking verbs without names do not count. Thus,  for  example,  if
+       backtracking  verbs  without  names do not count. Thus, for example, if
        the matching path contains (*MARK:A)(*PRUNE), the name "A" is returned.
        After a "no match" or a partial match, the last encountered name is re-
        turned. For example, consider this pattern:
 
          ^(*MARK:A)((*MARK:B)a|b)c
 
-       When  it  matches "bc", the returned name is A. The B mark is "seen" in
-       the first branch of the group, but it is not on the matching  path.  On
-       the  other  hand,  when  this pattern fails to match "bx", the returned
+       When it matches "bc", the returned name is A. The B mark is  "seen"  in
+       the  first  branch of the group, but it is not on the matching path. On
+       the other hand, when this pattern fails to  match  "bx",  the  returned
        name is B.
 
-       Warning: By default, certain start-of-match optimizations are  used  to
-       give  a  fast "no match" result in some situations. For example, if the
-       anchoring is removed from the pattern above, there is an initial  check
-       for  the presence of "c" in the subject before running the matching en-
+       Warning:  By  default, certain start-of-match optimizations are used to
+       give a fast "no match" result in some situations. For example,  if  the
+       anchoring  is removed from the pattern above, there is an initial check
+       for the presence of "c" in the subject before running the matching  en-
        gine. This check fails for "bx", causing a match failure without seeing
-       any  marks. You can disable the start-of-match optimizations by setting
-       the PCRE2_NO_START_OPTIMIZE option for pcre2_compile() or  by  starting
+       any marks. You can disable the start-of-match optimizations by  setting
+       the  PCRE2_NO_START_OPTIMIZE  option for pcre2_compile() or by starting
        the pattern with (*NO_START_OPT).
 
-       After  a  successful  match, a partial match, or one of the invalid UTF
-       errors (for example, PCRE2_ERROR_UTF8_ERR5), pcre2_get_startchar()  can
+       After a successful match, a partial match, or one of  the  invalid  UTF
+       errors  (for example, PCRE2_ERROR_UTF8_ERR5), pcre2_get_startchar() can
        be called. After a successful or partial match it returns the code unit
-       offset of the character at which the match started. For  a  non-partial
-       match,  this can be different to the value of ovector[0] if the pattern
-       contains the \K escape sequence. After a partial match,  however,  this
-       value  is  always the same as ovector[0] because \K does not affect the
+       offset  of  the character at which the match started. For a non-partial
+       match, this can be different to the value of ovector[0] if the  pattern
+       contains  the  \K escape sequence. After a partial match, however, this
+       value is always the same as ovector[0] because \K does not  affect  the
        result of a partial match.
 
-       After a UTF check failure, pcre2_get_startchar() can be used to  obtain
+       After  a UTF check failure, pcre2_get_startchar() can be used to obtain
        the code unit offset of the invalid UTF character. Details are given in
        the pcre2unicode page.
 
 
 ERROR RETURNS FROM pcre2_match()
 
-       If pcre2_match() fails, it returns a negative number. This can be  con-
-       verted  to a text string by calling the pcre2_get_error_message() func-
-       tion (see "Obtaining a textual error message" below).   Negative  error
-       codes  are  also  returned  by other functions, and are documented with
-       them. The codes are given names in the header file. If UTF checking  is
+       If  pcre2_match() fails, it returns a negative number. This can be con-
+       verted to a text string by calling the pcre2_get_error_message()  func-
+       tion  (see  "Obtaining a textual error message" below).  Negative error
+       codes are also returned by other functions,  and  are  documented  with
+       them.  The codes are given names in the header file. If UTF checking is
        in force and an invalid UTF subject string is detected, one of a number
-       of UTF-specific negative error codes is returned. Details are given  in
-       the  pcre2unicode  page. The following are the other errors that may be
+       of  UTF-specific negative error codes is returned. Details are given in
+       the pcre2unicode page. The following are the other errors that  may  be
        returned by pcre2_match():
 
          PCRE2_ERROR_NOMATCH
@@ -2976,20 +2983,20 @@ ERROR RETURNS FROM pcre2_match()
 
          PCRE2_ERROR_PARTIAL
 
-       The subject string did not match, but it did match partially.  See  the
+       The  subject  string did not match, but it did match partially. See the
        pcre2partial documentation for details of partial matching.
 
          PCRE2_ERROR_BADMAGIC
 
        PCRE2 stores a 4-byte "magic number" at the start of the compiled code,
-       to catch the case when it is passed a junk pointer. This is  the  error
+       to  catch  the case when it is passed a junk pointer. This is the error
        that is returned when the magic number is not present.
 
          PCRE2_ERROR_BADMODE
 
-       This  error is given when a compiled pattern is passed to a function in
-       a library of a different code unit width, for example, a  pattern  com-
-       piled  by  the  8-bit  library  is passed to a 16-bit or 32-bit library
+       This error is given when a compiled pattern is passed to a function  in
+       a  library  of a different code unit width, for example, a pattern com-
+       piled by the 8-bit library is passed to  a  16-bit  or  32-bit  library
        function.
 
          PCRE2_ERROR_BADOFFSET
@@ -3003,15 +3010,15 @@ ERROR RETURNS FROM pcre2_match()
          PCRE2_ERROR_BADUTFOFFSET
 
        The UTF code unit sequence that was passed as a subject was checked and
-       found  to be valid (the PCRE2_NO_UTF_CHECK option was not set), but the
-       value of startoffset did not point to the beginning of a UTF  character
+       found to be valid (the PCRE2_NO_UTF_CHECK option was not set), but  the
+       value  of startoffset did not point to the beginning of a UTF character
        or the end of the subject.
 
          PCRE2_ERROR_CALLOUT
 
-       This  error  is never generated by pcre2_match() itself. It is provided
-       for use by callout  functions  that  want  to  cause  pcre2_match()  or
-       pcre2_callout_enumerate()  to  return a distinctive error code. See the
+       This error is never generated by pcre2_match() itself. It  is  provided
+       for  use  by  callout  functions  that  want  to cause pcre2_match() or
+       pcre2_callout_enumerate() to return a distinctive error code.  See  the
        pcre2callout documentation for details.
 
          PCRE2_ERROR_DEPTHLIMIT
@@ -3024,14 +3031,14 @@ ERROR RETURNS FROM pcre2_match()
 
          PCRE2_ERROR_INTERNAL
 
-       An unexpected internal error has occurred. This error could  be  caused
+       An  unexpected  internal error has occurred. This error could be caused
        by a bug in PCRE2 or by overwriting of the compiled pattern.
 
          PCRE2_ERROR_JIT_STACKLIMIT
 
        This error is returned when a pattern that was successfully studied us-
        ing JIT is being matched, but the memory available for the just-in-time
-       processing  stack  is  not large enough. See the pcre2jit documentation
+       processing stack is not large enough. See  the  pcre2jit  documentation
        for more details.
 
          PCRE2_ERROR_MATCHLIMIT
@@ -3040,11 +3047,11 @@ ERROR RETURNS FROM pcre2_match()
 
          PCRE2_ERROR_NOMEMORY
 
-       If a pattern contains many nested backtracking points, heap  memory  is
-       used  to  remember them. This error is given when the memory allocation
-       function (default or  custom)  fails.  Note  that  a  different  error,
-       PCRE2_ERROR_HEAPLIMIT,  is given if the amount of memory needed exceeds
-       the   heap   limit.   PCRE2_ERROR_NOMEMORY   is   also   returned    if
+       If  a  pattern contains many nested backtracking points, heap memory is
+       used to remember them. This error is given when the  memory  allocation
+       function  (default  or  custom)  fails.  Note  that  a different error,
+       PCRE2_ERROR_HEAPLIMIT, is given if the amount of memory needed  exceeds
+       the    heap   limit.   PCRE2_ERROR_NOMEMORY   is   also   returned   if
        PCRE2_COPY_MATCHED_SUBJECT is set and memory allocation fails.
 
          PCRE2_ERROR_NULL
@@ -3053,12 +3060,12 @@ ERROR RETURNS FROM pcre2_match()
 
          PCRE2_ERROR_RECURSELOOP
 
-       This  error  is  returned  when  pcre2_match() detects a recursion loop
-       within the pattern. Specifically, it means that either the  whole  pat-
+       This error is returned when  pcre2_match()  detects  a  recursion  loop
+       within  the  pattern. Specifically, it means that either the whole pat-
        tern or a capture group has been called recursively for the second time
-       at the same position in the subject string. Some simple  patterns  that
-       might  do  this are detected and faulted at compile time, but more com-
-       plicated cases, in particular mutual recursions between  two  different
+       at  the  same position in the subject string. Some simple patterns that
+       might do this are detected and faulted at compile time, but  more  com-
+       plicated  cases,  in particular mutual recursions between two different
        groups, cannot be detected until matching is attempted.
 
 
@@ -3067,20 +3074,20 @@ OBTAINING A TEXTUAL ERROR MESSAGE
        int pcre2_get_error_message(int errorcode, PCRE2_UCHAR *buffer,
          PCRE2_SIZE bufflen);
 
-       A  text  message  for  an  error code from any PCRE2 function (compile,
-       match, or auxiliary) can be obtained  by  calling  pcre2_get_error_mes-
-       sage().  The  code  is passed as the first argument, with the remaining
-       two arguments specifying a code unit buffer  and  its  length  in  code
-       units,  into  which the text message is placed. The message is returned
-       in code units of the appropriate width for the library  that  is  being
+       A text message for an error code  from  any  PCRE2  function  (compile,
+       match,  or  auxiliary)  can be obtained by calling pcre2_get_error_mes-
+       sage(). The code is passed as the first argument,  with  the  remaining
+       two  arguments  specifying  a  code  unit buffer and its length in code
+       units, into which the text message is placed. The message  is  returned
+       in  code  units  of the appropriate width for the library that is being
        used.
 
-       The  returned message is terminated with a trailing zero, and the func-
-       tion returns the number of code  units  used,  excluding  the  trailing
+       The returned message is terminated with a trailing zero, and the  func-
+       tion  returns  the  number  of  code units used, excluding the trailing
        zero. If the error number is unknown, the negative error code PCRE2_ER-
-       ROR_BADDATA is returned. If the buffer is too  small,  the  message  is
+       ROR_BADDATA  is  returned.  If  the buffer is too small, the message is
        truncated (but still with a trailing zero), and the negative error code
-       PCRE2_ERROR_NOMEMORY is returned.  None of the messages are very  long;
+       PCRE2_ERROR_NOMEMORY  is returned.  None of the messages are very long;
        a buffer size of 120 code units is ample.
 
 
@@ -3099,39 +3106,39 @@ EXTRACTING CAPTURED SUBSTRINGS BY NUMBER
 
        void pcre2_substring_free(PCRE2_UCHAR *buffer);
 
-       Captured  substrings  can  be accessed directly by using the ovector as
+       Captured substrings can be accessed directly by using  the  ovector  as
        described above.  For convenience, auxiliary functions are provided for
-       extracting   captured  substrings  as  new,  separate,  zero-terminated
+       extracting  captured  substrings  as  new,  separate,   zero-terminated
        strings. A substring that contains a binary zero is correctly extracted
-       and  has  a  further  zero  added on the end, but the result is not, of
+       and has a further zero added on the end, but  the  result  is  not,  of
        course, a C string.
 
        The functions in this section identify substrings by number. The number
        zero refers to the entire matched substring, with higher numbers refer-
-       ring to substrings captured by parenthesized groups.  After  a  partial
-       match,  only  substring  zero  is  available. An attempt to extract any
-       other substring gives the error PCRE2_ERROR_PARTIAL. The  next  section
+       ring  to  substrings  captured by parenthesized groups. After a partial
+       match, only substring zero is available.  An  attempt  to  extract  any
+       other  substring  gives the error PCRE2_ERROR_PARTIAL. The next section
        describes similar functions for extracting captured substrings by name.
 
-       If  a  pattern uses the \K escape sequence within a positive assertion,
+       If a pattern uses the \K escape sequence within a  positive  assertion,
        the reported start of a successful match can be greater than the end of
-       the  match.   For  example,  if the pattern (?=ab\K) is matched against
-       "ab", the start and end offset values for the match are  2  and  0.  In
-       this  situation,  calling  these functions with a zero substring number
+       the match.  For example, if the pattern  (?=ab\K)  is  matched  against
+       "ab",  the  start  and  end offset values for the match are 2 and 0. In
+       this situation, calling these functions with a  zero  substring  number
        extracts a zero-length empty string.
 
-       You can find the length in code units of a captured  substring  without
-       extracting  it  by calling pcre2_substring_length_bynumber(). The first
-       argument is a pointer to the match data block, the second is the  group
-       number,  and the third is a pointer to a variable into which the length
-       is placed. If you just want to know whether or not  the  substring  has
+       You  can  find the length in code units of a captured substring without
+       extracting it by calling pcre2_substring_length_bynumber().  The  first
+       argument  is a pointer to the match data block, the second is the group
+       number, and the third is a pointer to a variable into which the  length
+       is  placed.  If  you just want to know whether or not the substring has
        been captured, you can pass the third argument as NULL.
 
-       The  pcre2_substring_copy_bynumber()  function  copies  a captured sub-
-       string into a supplied buffer,  whereas  pcre2_substring_get_bynumber()
-       copies  it  into  new memory, obtained using the same memory allocation
-       function that was used for the match data block. The  first  two  argu-
-       ments  of  these  functions are a pointer to the match data block and a
+       The pcre2_substring_copy_bynumber() function  copies  a  captured  sub-
+       string  into  a supplied buffer, whereas pcre2_substring_get_bynumber()
+       copies it into new memory, obtained using the  same  memory  allocation
+       function  that  was  used for the match data block. The first two argu-
+       ments of these functions are a pointer to the match data  block  and  a
        capture group number.
 
        The final arguments of pcre2_substring_copy_bynumber() are a pointer to
@@ -3140,25 +3147,25 @@ EXTRACTING CAPTURED SUBSTRINGS BY NUMBER
        for the extracted substring, excluding the terminating zero.
 
        For pcre2_substring_get_bynumber() the third and fourth arguments point
-       to variables that are updated with a pointer to the new memory and  the
-       number  of  code units that comprise the substring, again excluding the
-       terminating zero. When the substring is no longer  needed,  the  memory
+       to  variables that are updated with a pointer to the new memory and the
+       number of code units that comprise the substring, again  excluding  the
+       terminating  zero.  When  the substring is no longer needed, the memory
        should be freed by calling pcre2_substring_free().
 
-       The  return  value  from  all these functions is zero for success, or a
-       negative error code. If the pattern match  failed,  the  match  failure
-       code  is returned.  If a substring number greater than zero is used af-
-       ter a partial match, PCRE2_ERROR_PARTIAL is  returned.  Other  possible
+       The return value from all these functions is zero  for  success,  or  a
+       negative  error  code.  If  the pattern match failed, the match failure
+       code is returned.  If a substring number greater than zero is used  af-
+       ter  a  partial  match, PCRE2_ERROR_PARTIAL is returned. Other possible
        error codes are:
 
          PCRE2_ERROR_NOMEMORY
 
-       The  buffer  was  too small for pcre2_substring_copy_bynumber(), or the
+       The buffer was too small for  pcre2_substring_copy_bynumber(),  or  the
        attempt to get memory failed for pcre2_substring_get_bynumber().
 
          PCRE2_ERROR_NOSUBSTRING
 
-       There is no substring with that number in the  pattern,  that  is,  the
+       There  is  no  substring  with that number in the pattern, that is, the
        number is greater than the number of capturing parentheses.
 
          PCRE2_ERROR_UNAVAILABLE
@@ -3169,8 +3176,8 @@ EXTRACTING CAPTURED SUBSTRINGS BY NUMBER
 
          PCRE2_ERROR_UNSET
 
-       The  substring  did  not  participate in the match. For example, if the
-       pattern is (abc)|(def) and the subject is "def", and the  ovector  con-
+       The substring did not participate in the match.  For  example,  if  the
+       pattern  is  (abc)|(def) and the subject is "def", and the ovector con-
        tains at least two capturing slots, substring number 1 is unset.
 
 
@@ -3181,31 +3188,31 @@ EXTRACTING A LIST OF ALL CAPTURED SUBSTRINGS
 
        void pcre2_substring_list_free(PCRE2_SPTR *list);
 
-       The  pcre2_substring_list_get()  function  extracts  all available sub-
-       strings and builds a list of pointers to  them.  It  also  (optionally)
-       builds  a  second list that contains their lengths (in code units), ex-
-       cluding a terminating zero that is added to each of them. All  this  is
+       The pcre2_substring_list_get() function  extracts  all  available  sub-
+       strings  and  builds  a  list of pointers to them. It also (optionally)
+       builds a second list that contains their lengths (in code  units),  ex-
+       cluding  a  terminating zero that is added to each of them. All this is
        done in a single block of memory that is obtained using the same memory
        allocation function that was used to get the match data block.
 
-       This function must be called only after a successful match.  If  called
+       This  function  must be called only after a successful match. If called
        after a partial match, the error code PCRE2_ERROR_PARTIAL is returned.
 
-       The  address of the memory block is returned via listptr, which is also
+       The address of the memory block is returned via listptr, which is  also
        the start of the list of string pointers. The end of the list is marked
-       by  a  NULL pointer. The address of the list of lengths is returned via
-       lengthsptr. If your strings do not contain binary zeros and you do  not
+       by a NULL pointer. The address of the list of lengths is  returned  via
+       lengthsptr.  If your strings do not contain binary zeros and you do not
        therefore need the lengths, you may supply NULL as the lengthsptr argu-
-       ment to disable the creation of a list of lengths.  The  yield  of  the
-       function  is zero if all went well, or PCRE2_ERROR_NOMEMORY if the mem-
-       ory block could not be obtained. When the list is no longer needed,  it
+       ment  to  disable  the  creation of a list of lengths. The yield of the
+       function is zero if all went well, or PCRE2_ERROR_NOMEMORY if the  mem-
+       ory  block could not be obtained. When the list is no longer needed, it
        should be freed by calling pcre2_substring_list_free().
 
        If this function encounters a substring that is unset, which can happen
-       when capture group number n+1 matches some part  of  the  subject,  but
-       group  n has not been used at all, it returns an empty string. This can
+       when  capture  group  number  n+1 matches some part of the subject, but
+       group n has not been used at all, it returns an empty string. This  can
        be distinguished from a genuine zero-length substring by inspecting the
-       appropriate  offset in the ovector, which contain PCRE2_UNSET for unset
+       appropriate offset in the ovector, which contain PCRE2_UNSET for  unset
        substrings, or by calling pcre2_substring_length_bynumber().
 
 
@@ -3225,7 +3232,7 @@ EXTRACTING CAPTURED SUBSTRINGS BY NAME
 
        void pcre2_substring_free(PCRE2_UCHAR *buffer);
 
-       To extract a substring by name, you first have to find associated  num-
+       To  extract a substring by name, you first have to find associated num-
        ber.  For example, for this pattern:
 
          (a+)b(?\d+)...
@@ -3233,32 +3240,32 @@ EXTRACTING CAPTURED SUBSTRINGS BY NAME
        the number of the capture group called "xxx" is 2. If the name is known
        to be unique (PCRE2_DUPNAMES was not set), you can find the number from
        the name by calling pcre2_substring_number_from_name(). The first argu-
-       ment is the compiled pattern, and the second is the name. The yield  of
-       the  function  is the group number, PCRE2_ERROR_NOSUBSTRING if there is
-       no group with that name, or PCRE2_ERROR_NOUNIQUESUBSTRING if  there  is
-       more  than one group with that name.  Given the number, you can extract
-       the substring directly from the ovector, or use one of  the  "bynumber"
+       ment  is the compiled pattern, and the second is the name. The yield of
+       the function is the group number, PCRE2_ERROR_NOSUBSTRING if  there  is
+       no  group  with that name, or PCRE2_ERROR_NOUNIQUESUBSTRING if there is
+       more than one group with that name.  Given the number, you can  extract
+       the  substring  directly from the ovector, or use one of the "bynumber"
        functions described above.
 
-       For  convenience,  there are also "byname" functions that correspond to
+       For convenience, there are also "byname" functions that  correspond  to
        the "bynumber" functions, the only difference being that the second ar-
-       gument  is  a  name  instead  of a number. If PCRE2_DUPNAMES is set and
+       gument is a name instead of a number.  If  PCRE2_DUPNAMES  is  set  and
        there are duplicate names, these functions scan all the groups with the
-       given  name,  and  return  the  captured substring from the first named
+       given name, and return the captured  substring  from  the  first  named
        group that is set.
 
-       If there are no groups with the given name, PCRE2_ERROR_NOSUBSTRING  is
-       returned.  If  all  groups  with the name have numbers that are greater
+       If  there are no groups with the given name, PCRE2_ERROR_NOSUBSTRING is
+       returned. If all groups with the name have  numbers  that  are  greater
        than the number of slots in the ovector, PCRE2_ERROR_UNAVAILABLE is re-
-       turned.  If there is at least one group with a slot in the ovector, but
+       turned. If there is at least one group with a slot in the ovector,  but
        no group is found to be set, PCRE2_ERROR_UNSET is returned.
 
        Warning: If the pattern uses the (?| feature to set up multiple capture
-       groups  with  the same number, as described in the section on duplicate
+       groups with the same number, as described in the section  on  duplicate
        group numbers in the pcre2pattern page, you cannot use names to distin-
-       guish  the  different capture groups, because names are not included in
-       the compiled code. The matching process uses  only  numbers.  For  this
-       reason,  the  use  of  different  names for groups with the same number
+       guish the different capture groups, because names are not  included  in
+       the  compiled  code.  The  matching process uses only numbers. For this
+       reason, the use of different names for  groups  with  the  same  number
        causes an error at compile time.
 
 
@@ -3271,126 +3278,126 @@ CREATING A NEW STRING WITH SUBSTITUTIONS
          PCRE2_SIZE rlength, PCRE2_UCHAR *outputbuffer,
          PCRE2_SIZE *outlengthptr);
 
-       This function optionally calls pcre2_match() and then makes a  copy  of
-       the  subject  string in outputbuffer, replacing parts that were matched
-       with the replacement string, whose length is supplied in rlength.  This
-       can  be  given  as  PCRE2_ZERO_TERMINATED for a zero-terminated string.
+       This  function  optionally calls pcre2_match() and then makes a copy of
+       the subject string in outputbuffer, replacing parts that  were  matched
+       with  the replacement string, whose length is supplied in rlength. This
+       can be given as PCRE2_ZERO_TERMINATED  for  a  zero-terminated  string.
        There is an option (see PCRE2_SUBSTITUTE_REPLACEMENT_ONLY below) to re-
-       turn  just  the replacement string(s). The default action is to perform
-       just one replacement if the pattern matches, but  there  is  an  option
-       that  requests  multiple  replacements (see PCRE2_SUBSTITUTE_GLOBAL be-
+       turn just the replacement string(s). The default action is  to  perform
+       just  one  replacement  if  the pattern matches, but there is an option
+       that requests multiple replacements  (see  PCRE2_SUBSTITUTE_GLOBAL  be-
        low).
 
-       If successful, pcre2_substitute() returns the number  of  substitutions
-       that  were  carried out. This may be zero if no match was found, and is
-       never greater than one unless PCRE2_SUBSTITUTE_GLOBAL is set.  A  nega-
+       If  successful,  pcre2_substitute() returns the number of substitutions
+       that were carried out. This may be zero if no match was found,  and  is
+       never  greater  than one unless PCRE2_SUBSTITUTE_GLOBAL is set. A nega-
        tive value is returned if an error is detected.
 
-       Matches  in  which  a  \K item in a lookahead in the pattern causes the
-       match to end before it starts are not supported, and give  rise  to  an
+       Matches in which a \K item in a lookahead in  the  pattern  causes  the
+       match  to  end  before it starts are not supported, and give rise to an
        error return. For global replacements, matches in which \K in a lookbe-
-       hind causes the match to start earlier than the point that was  reached
+       hind  causes the match to start earlier than the point that was reached
        in the previous iteration are also not supported.
 
-       The  first  seven  arguments  of pcre2_substitute() are the same as for
+       The first seven arguments of pcre2_substitute() are  the  same  as  for
        pcre2_match(), except that the partial matching options are not permit-
-       ted,  and  match_data may be passed as NULL, in which case a match data
-       block is obtained and freed within this function, using memory  manage-
-       ment  functions from the match context, if provided, or else those that
+       ted, and match_data may be passed as NULL, in which case a  match  data
+       block  is obtained and freed within this function, using memory manage-
+       ment functions from the match context, if provided, or else those  that
        were used to allocate memory for the compiled code.
 
-       If match_data is not NULL and PCRE2_SUBSTITUTE_MATCHED is not set,  the
+       If  match_data is not NULL and PCRE2_SUBSTITUTE_MATCHED is not set, the
        provided block is used for all calls to pcre2_match(), and its contents
-       afterwards are the result of the final call. For global  changes,  this
+       afterwards  are  the result of the final call. For global changes, this
        will always be a no-match error. The contents of the ovector within the
        match data block may or may not have been changed.
 
-       As well as the usual options for pcre2_match(), a number of  additional
-       options  can be set in the options argument of pcre2_substitute().  One
-       such option is PCRE2_SUBSTITUTE_MATCHED. When this is set, an  external
-       match_data  block  must  be provided, and it must have been used for an
-       external call to pcre2_match(). The data in the match_data  block  (re-
+       As  well as the usual options for pcre2_match(), a number of additional
+       options can be set in the options argument of pcre2_substitute().   One
+       such  option is PCRE2_SUBSTITUTE_MATCHED. When this is set, an external
+       match_data block must be provided, and it must have been  used  for  an
+       external  call  to pcre2_match(). The data in the match_data block (re-
        turn code, offset vector) is used for the first substitution instead of
-       calling pcre2_match() from within pcre2_substitute().  This  allows  an
+       calling  pcre2_match()  from  within pcre2_substitute(). This allows an
        application to check for a match before choosing to substitute, without
        having to repeat the match.
 
-       The contents of the  externally  supplied  match  data  block  are  not
-       changed   when   PCRE2_SUBSTITUTE_MATCHED   is  set.  If  PCRE2_SUBSTI-
-       TUTE_GLOBAL is also set, pcre2_match() is called after the  first  sub-
-       stitution  to  check for further matches, but this is done using an in-
-       ternally obtained match data block, thus always  leaving  the  external
+       The  contents  of  the  externally  supplied  match  data block are not
+       changed  when  PCRE2_SUBSTITUTE_MATCHED  is   set.   If   PCRE2_SUBSTI-
+       TUTE_GLOBAL  is  also set, pcre2_match() is called after the first sub-
+       stitution to check for further matches, but this is done using  an  in-
+       ternally  obtained  match  data block, thus always leaving the external
        block unchanged.
 
-       The  code  argument is not used for matching before the first substitu-
-       tion when PCRE2_SUBSTITUTE_MATCHED is set, but  it  must  be  provided,
-       even  when  PCRE2_SUBSTITUTE_GLOBAL is not set, because it contains in-
+       The code argument is not used for matching before the  first  substitu-
+       tion  when  PCRE2_SUBSTITUTE_MATCHED  is  set, but it must be provided,
+       even when PCRE2_SUBSTITUTE_GLOBAL is not set, because it  contains  in-
        formation such as the UTF setting and the number of capturing parenthe-
        ses in the pattern.
 
-       The  default  action  of  pcre2_substitute() is to return a copy of the
+       The default action of pcre2_substitute() is to return  a  copy  of  the
        subject string with matched substrings replaced. However, if PCRE2_SUB-
-       STITUTE_REPLACEMENT_ONLY  is  set,  only the replacement substrings are
+       STITUTE_REPLACEMENT_ONLY is set, only the  replacement  substrings  are
        returned. In the global case, multiple replacements are concatenated in
-       the  output  buffer.  Substitution  callouts (see below) can be used to
+       the output buffer. Substitution callouts (see below)  can  be  used  to
        separate them if necessary.
 
-       The outlengthptr argument of pcre2_substitute() must point to  a  vari-
-       able  that contains the length, in code units, of the output buffer. If
-       the function is successful, the value is updated to contain the  length
-       in  code  units  of the new string, excluding the trailing zero that is
+       The  outlengthptr  argument of pcre2_substitute() must point to a vari-
+       able that contains the length, in code units, of the output buffer.  If
+       the  function is successful, the value is updated to contain the length
+       in code units of the new string, excluding the trailing  zero  that  is
        automatically added.
 
-       If the function is not successful, the value set via  outlengthptr  de-
-       pends  on  the  type  of  error.  For  syntax errors in the replacement
+       If  the  function is not successful, the value set via outlengthptr de-
+       pends on the type of  error.  For  syntax  errors  in  the  replacement
        string, the value is the offset in the replacement string where the er-
-       ror  was  detected.  For  other errors, the value is PCRE2_UNSET by de-
+       ror was detected. For other errors, the value  is  PCRE2_UNSET  by  de-
        fault. This includes the case of the output buffer being too small, un-
        less PCRE2_SUBSTITUTE_OVERFLOW_LENGTH is set.
 
-       PCRE2_SUBSTITUTE_OVERFLOW_LENGTH  changes  what happens when the output
+       PCRE2_SUBSTITUTE_OVERFLOW_LENGTH changes what happens when  the  output
        buffer is too small. The default action is to return PCRE2_ERROR_NOMEM-
-       ORY  immediately.  If  this  option is set, however, pcre2_substitute()
+       ORY immediately. If this option  is  set,  however,  pcre2_substitute()
        continues to go through the motions of matching and substituting (with-
-       out,  of course, writing anything) in order to compute the size of buf-
-       fer that is needed. This value is  passed  back  via  the  outlengthptr
-       variable,  with  the  result  of  the  function  still  being PCRE2_ER-
+       out, of course, writing anything) in order to compute the size of  buf-
+       fer  that  is  needed.  This  value is passed back via the outlengthptr
+       variable, with  the  result  of  the  function  still  being  PCRE2_ER-
        ROR_NOMEMORY.
 
-       Passing a buffer size of zero is a permitted way  of  finding  out  how
-       much  memory  is needed for given substitution. However, this does mean
+       Passing  a  buffer  size  of zero is a permitted way of finding out how
+       much memory is needed for given substitution. However, this  does  mean
        that the entire operation is carried out twice. Depending on the appli-
-       cation,  it  may  be more efficient to allocate a large buffer and free
-       the  excess  afterwards,  instead   of   using   PCRE2_SUBSTITUTE_OVER-
+       cation, it may be more efficient to allocate a large  buffer  and  free
+       the   excess   afterwards,   instead  of  using  PCRE2_SUBSTITUTE_OVER-
        FLOW_LENGTH.
 
-       The  replacement  string,  which  is interpreted as a UTF string in UTF
-       mode, is checked for UTF validity unless PCRE2_NO_UTF_CHECK is set.  An
+       The replacement string, which is interpreted as a  UTF  string  in  UTF
+       mode,  is checked for UTF validity unless PCRE2_NO_UTF_CHECK is set. An
        invalid UTF replacement string causes an immediate return with the rel-
        evant UTF error code.
 
-       If PCRE2_SUBSTITUTE_LITERAL is set, the replacement string is  not  in-
+       If  PCRE2_SUBSTITUTE_LITERAL  is set, the replacement string is not in-
        terpreted in any way. By default, however, a dollar character is an es-
-       cape character that can specify the insertion of characters  from  cap-
-       ture  groups  and names from (*MARK) or other control verbs in the pat-
+       cape  character  that can specify the insertion of characters from cap-
+       ture groups and names from (*MARK) or other control verbs in  the  pat-
        tern. The following forms are always recognized:
 
          $$                  insert a dollar character
          $ or ${}      insert the contents of group 
          $*MARK or ${*MARK}  insert a control verb name
 
-       Either a group number or a group name  can  be  given  for  .  Curly
-       brackets  are  required only if the following character would be inter-
+       Either  a  group  number  or  a  group name can be given for . Curly
+       brackets are required only if the following character would  be  inter-
        preted as part of the number or name. The number may be zero to include
-       the  entire  matched  string.   For  example,  if  the pattern a(b)c is
-       matched with "=abc=" and the replacement string "+$1$0$1+", the  result
+       the entire matched string.   For  example,  if  the  pattern  a(b)c  is
+       matched  with "=abc=" and the replacement string "+$1$0$1+", the result
        is "=+babcb+=".
 
-       $*MARK  inserts the name from the last encountered backtracking control
-       verb on the matching path that has a name. (*MARK) must always  include
-       a  name,  but  the  other  verbs  need not. For example, in the case of
+       $*MARK inserts the name from the last encountered backtracking  control
+       verb  on the matching path that has a name. (*MARK) must always include
+       a name, but the other verbs need not.  For  example,  in  the  case  of
        (*MARK:A)(*PRUNE) the name inserted is "A", but for (*MARK:A)(*PRUNE:B)
-       the  relevant  name is "B". This facility can be used to perform simple
+       the relevant name is "B". This facility can be used to  perform  simple
        simultaneous substitutions, as this pcre2test example shows:
 
          /(*MARK:pear)apple|(*MARK:orange)lemon/g,replace=${*MARK}
@@ -3398,15 +3405,15 @@ CREATING A NEW STRING WITH SUBSTITUTIONS
           2: pear orange
 
        PCRE2_SUBSTITUTE_GLOBAL causes the function to iterate over the subject
-       string,  replacing every matching substring. If this option is not set,
-       only the first matching substring is replaced. The search  for  matches
-       takes  place in the original subject string (that is, previous replace-
-       ments do not affect it).  Iteration is  implemented  by  advancing  the
-       startoffset  value  for  each search, which is always passed the entire
+       string, replacing every matching substring. If this option is not  set,
+       only  the  first matching substring is replaced. The search for matches
+       takes place in the original subject string (that is, previous  replace-
+       ments  do  not  affect  it).  Iteration is implemented by advancing the
+       startoffset value for each search, which is always  passed  the  entire
        subject string. If an offset limit is set in the match context, search-
        ing stops when that limit is reached.
 
-       You  can  restrict  the effect of a global substitution to a portion of
+       You can restrict the effect of a global substitution to  a  portion  of
        the subject string by setting either or both of startoffset and an off-
        set limit. Here is a pcre2test example:
 
@@ -3414,73 +3421,73 @@ CREATING A NEW STRING WITH SUBSTITUTIONS
          ABC ABC ABC ABC\=offset=3,offset_limit=12
           2: ABC A!C A!C ABC
 
-       When  continuing  with  global substitutions after matching a substring
+       When continuing with global substitutions after  matching  a  substring
        with zero length, an attempt to find a non-empty match at the same off-
        set is performed.  If this is not successful, the offset is advanced by
        one character except when CRLF is a valid newline sequence and the next
-       two  characters are CR, LF. In this case, the offset is advanced by two
+       two characters are CR, LF. In this case, the offset is advanced by  two
        characters.
 
        PCRE2_SUBSTITUTE_UNKNOWN_UNSET causes references to capture groups that
        do not appear in the pattern to be treated as unset groups. This option
-       should be used with care, because it means that a typo in a group  name
+       should  be used with care, because it means that a typo in a group name
        or number no longer causes the PCRE2_ERROR_NOSUBSTRING error.
 
        PCRE2_SUBSTITUTE_UNSET_EMPTY causes unset capture groups (including un-
-       known groups when PCRE2_SUBSTITUTE_UNKNOWN_UNSET is set) to be  treated
-       as  empty  strings  when inserted as described above. If this option is
+       known  groups when PCRE2_SUBSTITUTE_UNKNOWN_UNSET is set) to be treated
+       as empty strings when inserted as described above. If  this  option  is
        not set, an attempt to insert an unset group causes the PCRE2_ERROR_UN-
-       SET  error.  This  option  does not influence the extended substitution
+       SET error. This option does not  influence  the  extended  substitution
        syntax described below.
 
-       PCRE2_SUBSTITUTE_EXTENDED causes extra processing to be applied to  the
-       replacement  string.  Without this option, only the dollar character is
-       special, and only the group insertion forms  listed  above  are  valid.
+       PCRE2_SUBSTITUTE_EXTENDED  causes extra processing to be applied to the
+       replacement string. Without this option, only the dollar  character  is
+       special,  and  only  the  group insertion forms listed above are valid.
        When PCRE2_SUBSTITUTE_EXTENDED is set, two things change:
 
-       Firstly,  backslash in a replacement string is interpreted as an escape
+       Firstly, backslash in a replacement string is interpreted as an  escape
        character. The usual forms such as \n or \x{ddd} can be used to specify
-       particular  character codes, and backslash followed by any non-alphanu-
-       meric character quotes that character. Extended quoting  can  be  coded
+       particular character codes, and backslash followed by any  non-alphanu-
+       meric  character  quotes  that character. Extended quoting can be coded
        using \Q...\E, exactly as in pattern strings.
 
-       There  are  also four escape sequences for forcing the case of inserted
-       letters.  The insertion mechanism has three states:  no  case  forcing,
+       There are also four escape sequences for forcing the case  of  inserted
+       letters.   The  insertion  mechanism has three states: no case forcing,
        force upper case, and force lower case. The escape sequences change the
        current state: \U and \L change to upper or lower case forcing, respec-
-       tively,  and  \E (when not terminating a \Q quoted sequence) reverts to
-       no case forcing. The sequences \u and \l force the next  character  (if
-       it  is  a  letter)  to  upper or lower case, respectively, and then the
+       tively, and \E (when not terminating a \Q quoted sequence)  reverts  to
+       no  case  forcing. The sequences \u and \l force the next character (if
+       it is a letter) to upper or lower  case,  respectively,  and  then  the
        state automatically reverts to no case forcing. Case forcing applies to
-       all  inserted  characters, including those from capture groups and let-
-       ters within \Q...\E quoted sequences. If either PCRE2_UTF or  PCRE2_UCP
-       was  set when the pattern was compiled, Unicode properties are used for
+       all inserted  characters, including those from capture groups and  let-
+       ters  within \Q...\E quoted sequences. If either PCRE2_UTF or PCRE2_UCP
+       was set when the pattern was compiled, Unicode properties are used  for
        case forcing characters whose code points are greater than 127.
 
        Note that case forcing sequences such as \U...\E do not nest. For exam-
-       ple,  the  result of processing "\Uaa\LBB\Ecc\E" is "AAbbcc"; the final
-       \E has no effect. Note  also  that  the  PCRE2_ALT_BSUX  and  PCRE2_EX-
+       ple, the result of processing "\Uaa\LBB\Ecc\E" is "AAbbcc";  the  final
+       \E  has  no  effect.  Note  also  that the PCRE2_ALT_BSUX and PCRE2_EX-
        TRA_ALT_BSUX options do not apply to replacement strings.
 
-       The  second  effect of setting PCRE2_SUBSTITUTE_EXTENDED is to add more
-       flexibility to capture group substitution. The  syntax  is  similar  to
+       The second effect of setting PCRE2_SUBSTITUTE_EXTENDED is to  add  more
+       flexibility  to  capture  group  substitution. The syntax is similar to
        that used by Bash:
 
          ${:-}
          ${:+:}
 
-       As  before,   may be a group number or a name. The first form speci-
-       fies a default value. If group  is set, its value  is  inserted;  if
-       not,    is  expanded  and  the result inserted. The second form
-       specifies strings that are expanded and inserted when group  is  set
-       or  unset,  respectively. The first form is just a convenient shorthand
+       As before,  may be a group number or a name. The first  form  speci-
+       fies  a  default  value. If group  is set, its value is inserted; if
+       not,  is expanded and the  result  inserted.  The  second  form
+       specifies  strings that are expanded and inserted when group  is set
+       or unset, respectively. The first form is just a  convenient  shorthand
        for
 
          ${:+${}:}
 
-       Backslash can be used to escape colons and closing  curly  brackets  in
-       the  replacement  strings.  A change of the case forcing state within a
-       replacement string remains  in  force  afterwards,  as  shown  in  this
+       Backslash  can  be  used to escape colons and closing curly brackets in
+       the replacement strings. A change of the case forcing  state  within  a
+       replacement  string  remains  in  force  afterwards,  as  shown in this
        pcre2test example:
 
          /(some)?(body)/substitute_extended,replace=${1:+\U:\L}HeLLo
@@ -3489,8 +3496,8 @@ CREATING A NEW STRING WITH SUBSTITUTIONS
              somebody
           1: HELLO
 
-       The  PCRE2_SUBSTITUTE_UNSET_EMPTY option does not affect these extended
-       substitutions. However, PCRE2_SUBSTITUTE_UNKNOWN_UNSET does  cause  un-
+       The PCRE2_SUBSTITUTE_UNSET_EMPTY option does not affect these  extended
+       substitutions.  However,  PCRE2_SUBSTITUTE_UNKNOWN_UNSET does cause un-
        known groups in the extended syntax forms to be treated as unset.
 
        If  PCRE2_SUBSTITUTE_LITERAL  is  set,  PCRE2_SUBSTITUTE_UNKNOWN_UNSET,
@@ -3499,37 +3506,37 @@ CREATING A NEW STRING WITH SUBSTITUTIONS
 
    Substitution errors
 
-       In  the  event of an error, pcre2_substitute() returns a negative error
-       code. Except for PCRE2_ERROR_NOMATCH (which is never returned),  errors
+       In the event of an error, pcre2_substitute() returns a  negative  error
+       code.  Except for PCRE2_ERROR_NOMATCH (which is never returned), errors
        from pcre2_match() are passed straight back.
 
        PCRE2_ERROR_NOSUBSTRING is returned for a non-existent substring inser-
        tion, unless PCRE2_SUBSTITUTE_UNKNOWN_UNSET is set.
 
        PCRE2_ERROR_UNSET is returned for an unset substring insertion (includ-
-       ing  an  unknown  substring when PCRE2_SUBSTITUTE_UNKNOWN_UNSET is set)
-       when the simple (non-extended) syntax is used and  PCRE2_SUBSTITUTE_UN-
+       ing an unknown substring when  PCRE2_SUBSTITUTE_UNKNOWN_UNSET  is  set)
+       when  the simple (non-extended) syntax is used and PCRE2_SUBSTITUTE_UN-
        SET_EMPTY is not set.
 
-       PCRE2_ERROR_NOMEMORY  is  returned  if  the  output  buffer  is not big
+       PCRE2_ERROR_NOMEMORY is returned  if  the  output  buffer  is  not  big
        enough. If the PCRE2_SUBSTITUTE_OVERFLOW_LENGTH option is set, the size
-       of  buffer  that is needed is returned via outlengthptr. Note that this
+       of buffer that is needed is returned via outlengthptr. Note  that  this
        does not happen by default.
 
        PCRE2_ERROR_NULL is returned if PCRE2_SUBSTITUTE_MATCHED is set but the
        match_data argument is NULL.
 
-       PCRE2_ERROR_BADREPLACEMENT  is  used for miscellaneous syntax errors in
-       the replacement string, with more  particular  errors  being  PCRE2_ER-
+       PCRE2_ERROR_BADREPLACEMENT is used for miscellaneous syntax  errors  in
+       the  replacement  string,  with  more particular errors being PCRE2_ER-
        ROR_BADREPESCAPE (invalid escape sequence), PCRE2_ERROR_REPMISSINGBRACE
-       (closing curly bracket not found), PCRE2_ERROR_BADSUBSTITUTION  (syntax
-       error  in  extended group substitution), and PCRE2_ERROR_BADSUBSPATTERN
+       (closing  curly bracket not found), PCRE2_ERROR_BADSUBSTITUTION (syntax
+       error in extended group substitution),  and  PCRE2_ERROR_BADSUBSPATTERN
        (the pattern match ended before it started or the match started earlier
-       than  the  current  position  in the subject, which can happen if \K is
+       than the current position in the subject, which can  happen  if  \K  is
        used in an assertion).
 
        As for all PCRE2 errors, a text message that describes the error can be
-       obtained  by  calling  the pcre2_get_error_message() function (see "Ob-
+       obtained by calling the pcre2_get_error_message()  function  (see  "Ob-
        taining a textual error message" above).
 
    Substitution callouts
@@ -3538,15 +3545,15 @@ CREATING A NEW STRING WITH SUBSTITUTIONS
          int (*callout_function)(pcre2_substitute_callout_block *, void *),
          void *callout_data);
 
-       The pcre2_set_substitution_callout() function can be used to specify  a
-       callout  function for pcre2_substitute(). This information is passed in
+       The  pcre2_set_substitution_callout() function can be used to specify a
+       callout function for pcre2_substitute(). This information is passed  in
        a match context. The callout function is called after each substitution
        has been processed, but it can cause the replacement not to happen. The
-       callout function is not called for simulated substitutions that  happen
+       callout  function is not called for simulated substitutions that happen
        as a result of the PCRE2_SUBSTITUTE_OVERFLOW_LENGTH option.
 
        The first argument of the callout function is a pointer to a substitute
-       callout block structure, which contains the following fields, not  nec-
+       callout  block structure, which contains the following fields, not nec-
        essarily in this order:
 
          uint32_t    version;
@@ -3557,34 +3564,34 @@ CREATING A NEW STRING WITH SUBSTITUTIONS
          uint32_t    oveccount;
          PCRE2_SIZE  output_offsets[2];
 
-       The  version field contains the version number of the block format. The
-       current version is 0. The version number will  increase  in  future  if
-       more  fields are added, but the intention is never to remove any of the
+       The version field contains the version number of the block format.  The
+       current  version  is  0.  The version number will increase in future if
+       more fields are added, but the intention is never to remove any of  the
        existing fields.
 
        The subscount field is the number of the current match. It is 1 for the
        first callout, 2 for the second, and so on. The input and output point-
        ers are copies of the values passed to pcre2_substitute().
 
-       The ovector field points to the ovector, which contains the  result  of
+       The  ovector  field points to the ovector, which contains the result of
        the most recent match. The oveccount field contains the number of pairs
        that are set in the ovector, and is always greater than zero.
 
-       The output_offsets vector contains the offsets of  the  replacement  in
-       the  output  string. This has already been processed for dollar and (if
+       The  output_offsets  vector  contains the offsets of the replacement in
+       the output string. This has already been processed for dollar  and  (if
        requested) backslash substitutions as described above.
 
-       The second argument of the callout function  is  the  value  passed  as
-       callout_data  when  the  function was registered. The value returned by
+       The  second  argument  of  the  callout function is the value passed as
+       callout_data when the function was registered. The  value  returned  by
        the callout function is interpreted as follows:
 
-       If the value is zero, the replacement is accepted, and,  if  PCRE2_SUB-
-       STITUTE_GLOBAL  is set, processing continues with a search for the next
-       match. If the value is not zero, the current  replacement  is  not  ac-
-       cepted.  If  the  value is greater than zero, processing continues when
-       PCRE2_SUBSTITUTE_GLOBAL is set. Otherwise (the value is less than  zero
-       or  PCRE2_SUBSTITUTE_GLOBAL  is  not set), the the rest of the input is
-       copied to the output and the call to pcre2_substitute() exits,  return-
+       If  the  value is zero, the replacement is accepted, and, if PCRE2_SUB-
+       STITUTE_GLOBAL is set, processing continues with a search for the  next
+       match.  If  the  value  is not zero, the current replacement is not ac-
+       cepted. If the value is greater than zero,  processing  continues  when
+       PCRE2_SUBSTITUTE_GLOBAL  is set. Otherwise (the value is less than zero
+       or PCRE2_SUBSTITUTE_GLOBAL is not set), the the rest of  the  input  is
+       copied  to the output and the call to pcre2_substitute() exits, return-
        ing the number of matches so far.
 
 
@@ -3593,56 +3600,56 @@ DUPLICATE CAPTURE GROUP NAMES
        int pcre2_substring_nametable_scan(const pcre2_code *code,
          PCRE2_SPTR name, PCRE2_SPTR *first, PCRE2_SPTR *last);
 
-       When  a  pattern  is compiled with the PCRE2_DUPNAMES option, names for
-       capture groups are not required to be unique. Duplicate names  are  al-
-       ways  allowed for groups with the same number, created by using the (?|
+       When a pattern is compiled with the PCRE2_DUPNAMES  option,  names  for
+       capture  groups  are not required to be unique. Duplicate names are al-
+       ways allowed for groups with the same number, created by using the  (?|
        feature. Indeed, if such groups are named, they are required to use the
        same names.
 
-       Normally,  patterns  that  use duplicate names are such that in any one
-       match, only one of each set of identically-named  groups  participates.
+       Normally, patterns that use duplicate names are such that  in  any  one
+       match,  only  one of each set of identically-named groups participates.
        An example is shown in the pcre2pattern documentation.
 
-       When   duplicates   are   present,   pcre2_substring_copy_byname()  and
-       pcre2_substring_get_byname() return the first  substring  corresponding
-       to  the given name that is set. Only if none are set is PCRE2_ERROR_UN-
-       SET is returned. The  pcre2_substring_number_from_name()  function  re-
-       turns  the error PCRE2_ERROR_NOUNIQUESUBSTRING when there are duplicate
+       When  duplicates   are   present,   pcre2_substring_copy_byname()   and
+       pcre2_substring_get_byname()  return  the first substring corresponding
+       to the given name that is set. Only if none are set is  PCRE2_ERROR_UN-
+       SET  is  returned.  The pcre2_substring_number_from_name() function re-
+       turns the error PCRE2_ERROR_NOUNIQUESUBSTRING when there are  duplicate
        names.
 
-       If you want to get full details of all captured substrings for a  given
-       name,  you  must use the pcre2_substring_nametable_scan() function. The
-       first argument is the compiled pattern, and the second is the name.  If
-       the  third  and fourth arguments are NULL, the function returns a group
+       If  you want to get full details of all captured substrings for a given
+       name, you must use the pcre2_substring_nametable_scan()  function.  The
+       first  argument is the compiled pattern, and the second is the name. If
+       the third and fourth arguments are NULL, the function returns  a  group
        number for a unique name, or PCRE2_ERROR_NOUNIQUESUBSTRING otherwise.
 
        When the third and fourth arguments are not NULL, they must be pointers
-       to  variables  that are updated by the function. After it has run, they
+       to variables that are updated by the function. After it has  run,  they
        point to the first and last entries in the name-to-number table for the
-       given  name,  and the function returns the length of each entry in code
-       units. In both cases, PCRE2_ERROR_NOSUBSTRING is returned if there  are
+       given name, and the function returns the length of each entry  in  code
+       units.  In both cases, PCRE2_ERROR_NOSUBSTRING is returned if there are
        no entries for the given name.
 
        The format of the name table is described above in the section entitled
-       Information about a pattern. Given all the  relevant  entries  for  the
-       name,  you  can  extract  each of their numbers, and hence the captured
+       Information  about  a  pattern.  Given all the relevant entries for the
+       name, you can extract each of their numbers,  and  hence  the  captured
        data.
 
 
 FINDING ALL POSSIBLE MATCHES AT ONE POSITION
 
-       The traditional matching function uses a  similar  algorithm  to  Perl,
-       which  stops when it finds the first match at a given point in the sub-
+       The  traditional  matching  function  uses a similar algorithm to Perl,
+       which stops when it finds the first match at a given point in the  sub-
        ject. If you want to find all possible matches, or the longest possible
-       match  at  a  given  position,  consider using the alternative matching
-       function (see below) instead. If you cannot use the  alternative  func-
+       match at a given position,  consider  using  the  alternative  matching
+       function  (see  below) instead. If you cannot use the alternative func-
        tion, you can kludge it up by making use of the callout facility, which
        is described in the pcre2callout documentation.
 
        What you have to do is to insert a callout right at the end of the pat-
-       tern.   When your callout function is called, extract and save the cur-
-       rent matched substring. Then return 1, which  forces  pcre2_match()  to
-       backtrack  and  try other alternatives. Ultimately, when it runs out of
+       tern.  When your callout function is called, extract and save the  cur-
+       rent  matched  substring.  Then return 1, which forces pcre2_match() to
+       backtrack and try other alternatives. Ultimately, when it runs  out  of
        matches, pcre2_match() will yield PCRE2_ERROR_NOMATCH.
 
 
@@ -3654,26 +3661,26 @@ MATCHING A PATTERN: THE ALTERNATIVE FUNCTION
          pcre2_match_context *mcontext,
          int *workspace, PCRE2_SIZE wscount);
 
-       The function pcre2_dfa_match() is called  to  match  a  subject  string
-       against  a  compiled pattern, using a matching algorithm that scans the
+       The  function  pcre2_dfa_match()  is  called  to match a subject string
+       against a compiled pattern, using a matching algorithm that  scans  the
        subject string just once (not counting lookaround assertions), and does
-       not  backtrack.  This has different characteristics to the normal algo-
-       rithm, and is not compatible with Perl. Some of the features  of  PCRE2
-       patterns  are  not  supported.  Nevertheless, there are times when this
-       kind of matching can be useful. For a discussion of  the  two  matching
+       not backtrack.  This has different characteristics to the normal  algo-
+       rithm,  and  is not compatible with Perl. Some of the features of PCRE2
+       patterns are not supported.  Nevertheless, there are  times  when  this
+       kind  of  matching  can be useful. For a discussion of the two matching
        algorithms, and a list of features that pcre2_dfa_match() does not sup-
        port, see the pcre2matching documentation.
 
-       The arguments for the pcre2_dfa_match() function are the  same  as  for
+       The  arguments  for  the pcre2_dfa_match() function are the same as for
        pcre2_match(), plus two extras. The ovector within the match data block
        is used in a different way, and this is described below. The other com-
-       mon  arguments  are used in the same way as for pcre2_match(), so their
+       mon arguments are used in the same way as for pcre2_match(),  so  their
        description is not repeated here.
 
-       The two additional arguments provide workspace for  the  function.  The
-       workspace  vector  should  contain at least 20 elements. It is used for
+       The  two  additional  arguments provide workspace for the function. The
+       workspace vector should contain at least 20 elements. It  is  used  for
        keeping  track  of  multiple  paths  through  the  pattern  tree.  More
-       workspace  is needed for patterns and subjects where there are a lot of
+       workspace is needed for patterns and subjects where there are a lot  of
        potential matches.
 
        Here is an example of a simple call to pcre2_dfa_match():
@@ -3693,45 +3700,45 @@ MATCHING A PATTERN: THE ALTERNATIVE FUNCTION
 
    Option bits for pcre_dfa_match()
 
-       The unused bits of the options argument for pcre2_dfa_match()  must  be
-       zero.   The   only   bits   that   may   be   set  are  PCRE2_ANCHORED,
-       PCRE2_COPY_MATCHED_SUBJECT, PCRE2_ENDANCHORED, PCRE2_NOTBOL,  PCRE2_NO-
+       The  unused  bits of the options argument for pcre2_dfa_match() must be
+       zero.  The  only   bits   that   may   be   set   are   PCRE2_ANCHORED,
+       PCRE2_COPY_MATCHED_SUBJECT,  PCRE2_ENDANCHORED, PCRE2_NOTBOL, PCRE2_NO-
        TEOL,   PCRE2_NOTEMPTY,   PCRE2_NOTEMPTY_ATSTART,   PCRE2_NO_UTF_CHECK,
-       PCRE2_PARTIAL_HARD,   PCRE2_PARTIAL_SOFT,    PCRE2_DFA_SHORTEST,    and
-       PCRE2_DFA_RESTART.  All but the last four of these are exactly the same
+       PCRE2_PARTIAL_HARD,    PCRE2_PARTIAL_SOFT,    PCRE2_DFA_SHORTEST,   and
+       PCRE2_DFA_RESTART. All but the last four of these are exactly the  same
        as for pcre2_match(), so their description is not repeated here.
 
          PCRE2_PARTIAL_HARD
          PCRE2_PARTIAL_SOFT
 
-       These have the same general effect as they do  for  pcre2_match(),  but
-       the  details are slightly different. When PCRE2_PARTIAL_HARD is set for
-       pcre2_dfa_match(), it returns PCRE2_ERROR_PARTIAL if  the  end  of  the
+       These  have  the  same general effect as they do for pcre2_match(), but
+       the details are slightly different. When PCRE2_PARTIAL_HARD is set  for
+       pcre2_dfa_match(),  it  returns  PCRE2_ERROR_PARTIAL  if the end of the
        subject is reached and there is still at least one matching possibility
        that requires additional characters. This happens even if some complete
-       matches  have  already  been found. When PCRE2_PARTIAL_SOFT is set, the
-       return code PCRE2_ERROR_NOMATCH is converted  into  PCRE2_ERROR_PARTIAL
-       if  the  end  of  the  subject  is reached, there have been no complete
+       matches have already been found. When PCRE2_PARTIAL_SOFT  is  set,  the
+       return  code  PCRE2_ERROR_NOMATCH is converted into PCRE2_ERROR_PARTIAL
+       if the end of the subject is  reached,  there  have  been  no  complete
        matches, but there is still at least one matching possibility. The por-
-       tion  of  the  string that was inspected when the longest partial match
+       tion of the string that was inspected when the  longest  partial  match
        was found is set as the first matching string in both cases. There is a
-       more  detailed  discussion  of partial and multi-segment matching, with
+       more detailed discussion of partial and  multi-segment  matching,  with
        examples, in the pcre2partial documentation.
 
          PCRE2_DFA_SHORTEST
 
-       Setting the PCRE2_DFA_SHORTEST option causes the matching algorithm  to
+       Setting  the PCRE2_DFA_SHORTEST option causes the matching algorithm to
        stop as soon as it has found one match. Because of the way the alterna-
-       tive algorithm works, this is necessarily the shortest  possible  match
+       tive  algorithm  works, this is necessarily the shortest possible match
        at the first possible matching point in the subject string.
 
          PCRE2_DFA_RESTART
 
-       When  pcre2_dfa_match() returns a partial match, it is possible to call
+       When pcre2_dfa_match() returns a partial match, it is possible to  call
        it again, with additional subject characters, and have it continue with
        the same match. The PCRE2_DFA_RESTART option requests this action; when
-       it is set, the workspace and wscount options must  reference  the  same
-       vector  as  before  because data about the match so far is left in them
+       it  is  set,  the workspace and wscount options must reference the same
+       vector as before because data about the match so far is  left  in  them
        after a partial match. There is more discussion of this facility in the
        pcre2partial documentation.
 
@@ -3739,8 +3746,8 @@ MATCHING A PATTERN: THE ALTERNATIVE FUNCTION
 
        When pcre2_dfa_match() succeeds, it may have matched more than one sub-
        string in the subject. Note, however, that all the matches from one run
-       of  the  function  start  at the same point in the subject. The shorter
-       matches are all initial substrings of the longer matches. For  example,
+       of the function start at the same point in  the  subject.  The  shorter
+       matches  are all initial substrings of the longer matches. For example,
        if the pattern
 
          <.*>
@@ -3755,80 +3762,80 @@ MATCHING A PATTERN: THE ALTERNATIVE FUNCTION
           
          
 
-       On  success,  the  yield of the function is a number greater than zero,
-       which is the number of matched substrings.  The  offsets  of  the  sub-
-       strings  are returned in the ovector, and can be extracted by number in
-       the same way as for pcre2_match(), but the numbers bear no relation  to
-       any  capture groups that may exist in the pattern, because DFA matching
+       On success, the yield of the function is a number  greater  than  zero,
+       which  is  the  number  of  matched substrings. The offsets of the sub-
+       strings are returned in the ovector, and can be extracted by number  in
+       the  same way as for pcre2_match(), but the numbers bear no relation to
+       any capture groups that may exist in the pattern, because DFA  matching
        does not support capturing.
 
-       Calls to the convenience functions that extract substrings by name  re-
+       Calls  to the convenience functions that extract substrings by name re-
        turn the error PCRE2_ERROR_DFA_UFUNC (unsupported function) if used af-
-       ter a DFA match. The convenience functions that extract  substrings  by
+       ter  a  DFA match. The convenience functions that extract substrings by
        number never return PCRE2_ERROR_NOSUBSTRING.
 
-       The  matched  strings  are  stored  in  the ovector in reverse order of
-       length; that is, the longest matching string is first.  If  there  were
-       too  many matches to fit into the ovector, the yield of the function is
+       The matched strings are stored in  the  ovector  in  reverse  order  of
+       length;  that  is,  the longest matching string is first. If there were
+       too many matches to fit into the ovector, the yield of the function  is
        zero, and the vector is filled with the longest matches.
 
-       NOTE: PCRE2's "auto-possessification" optimization usually  applies  to
-       character  repeats at the end of a pattern (as well as internally). For
-       example, the pattern "a\d+" is compiled as if it were "a\d++". For  DFA
-       matching,  this means that only one possible match is found. If you re-
+       NOTE:  PCRE2's  "auto-possessification" optimization usually applies to
+       character repeats at the end of a pattern (as well as internally).  For
+       example,  the pattern "a\d+" is compiled as if it were "a\d++". For DFA
+       matching, this means that only one possible match is found. If you  re-
        ally do want multiple matches in such cases, either use an ungreedy re-
-       peat  such as "a\d+?" or set the PCRE2_NO_AUTO_POSSESS option when com-
+       peat such as "a\d+?" or set the PCRE2_NO_AUTO_POSSESS option when  com-
        piling.
 
    Error returns from pcre2_dfa_match()
 
        The pcre2_dfa_match() function returns a negative number when it fails.
-       Many  of  the  errors  are  the same as for pcre2_match(), as described
+       Many of the errors are the same  as  for  pcre2_match(),  as  described
        above.  There are in addition the following errors that are specific to
        pcre2_dfa_match():
 
          PCRE2_ERROR_DFA_UITEM
 
-       This  return  is  given  if pcre2_dfa_match() encounters an item in the
-       pattern that it does not support, for instance, the use of \C in a  UTF
+       This return is given if pcre2_dfa_match() encounters  an  item  in  the
+       pattern  that it does not support, for instance, the use of \C in a UTF
        mode or a backreference.
 
          PCRE2_ERROR_DFA_UCOND
 
-       This  return  is given if pcre2_dfa_match() encounters a condition item
+       This return is given if pcre2_dfa_match() encounters a  condition  item
        that uses a backreference for the condition, or a test for recursion in
        a specific capture group. These are not supported.
 
          PCRE2_ERROR_DFA_UINVALID_UTF
 
-       This  return is given if pcre2_dfa_match() is called for a pattern that
-       was compiled with PCRE2_MATCH_INVALID_UTF. This is  not  supported  for
+       This return is given if pcre2_dfa_match() is called for a pattern  that
+       was  compiled  with  PCRE2_MATCH_INVALID_UTF. This is not supported for
        DFA matching.
 
          PCRE2_ERROR_DFA_WSSIZE
 
-       This  return  is  given  if  pcre2_dfa_match() runs out of space in the
+       This return is given if pcre2_dfa_match() runs  out  of  space  in  the
        workspace vector.
 
          PCRE2_ERROR_DFA_RECURSE
 
        When a recursion or subroutine call is processed, the matching function
-       calls  itself  recursively,  using  private  memory for the ovector and
-       workspace.  This error is given if the internal ovector  is  not  large
-       enough.  This  should  be  extremely  rare, as a vector of size 1000 is
+       calls itself recursively, using private  memory  for  the  ovector  and
+       workspace.   This  error  is given if the internal ovector is not large
+       enough. This should be extremely rare, as a  vector  of  size  1000  is
        used.
 
          PCRE2_ERROR_DFA_BADRESTART
 
-       When pcre2_dfa_match() is called  with  the  PCRE2_DFA_RESTART  option,
-       some  plausibility  checks  are  made on the contents of the workspace,
-       which should contain data about the previous partial match. If  any  of
+       When  pcre2_dfa_match()  is  called  with the PCRE2_DFA_RESTART option,
+       some plausibility checks are made on the  contents  of  the  workspace,
+       which  should  contain data about the previous partial match. If any of
        these checks fail, this error is given.
 
 
 SEE ALSO
 
-       pcre2build(3),    pcre2callout(3),    pcre2demo(3),   pcre2matching(3),
+       pcre2build(3),   pcre2callout(3),    pcre2demo(3),    pcre2matching(3),
        pcre2partial(3), pcre2posix(3), pcre2sample(3), pcre2unicode(3).
 
 
@@ -3841,7 +3848,7 @@ AUTHOR
 
 REVISION
 
-       Last updated: 28 August 2021
+       Last updated: 30 August 2021
        Copyright (c) 1997-2021 University of Cambridge.
 ------------------------------------------------------------------------------
  
@@ -5003,8 +5010,10 @@ DIFFERENCES BETWEEN PCRE2 AND PERL
        specified.
 
        16. From release 5.32.0, Perl locks out the use of \K in lookaround as-
-       sertions. In PCRE2, \K is acted on when it occurs  in  positive  asser-
-       tions, but is ignored in negative assertions.
+       sertions. From release 10.38 PCRE2 does the same by  default.  However,
+       there  is  an  option for re-enabling the previous behaviour. When this
+       option is set, \K is acted on when it occurs  in  positive  assertions,
+       but is ignored in negative assertions.
 
        17.  PCRE2  provides some extensions to the Perl regular expression fa-
        cilities.  Perl 5.10 included new features that  were  not  in  earlier
@@ -5072,14 +5081,14 @@ DIFFERENCES BETWEEN PCRE2 AND PERL
 AUTHOR
 
        Philip Hazel
-       University Computing Service
+       Retired from University Computing Service
        Cambridge, England.
 
 
 REVISION
 
-       Last updated: 06 October 2020
-       Copyright (c) 1997-2019 University of Cambridge.
+       Last updated: 30 August 2021
+       Copyright (c) 1997-2021 University of Cambridge.
 ------------------------------------------------------------------------------
  
  
@@ -7103,14 +7112,16 @@ BACKSLASH
 
        matches "foobar", the first substring is still set to "foo".
 
-       Perl  used  to document that the use of \K within lookaround assertions
-       is "not well defined", but from version 5.32.0 Perl  does  not  support
-       this  usage  at  all.  In PCRE2, \K is acted upon when it occurs inside
-       positive assertions, but is ignored in negative assertions.  Note  that
-       when  a  pattern  such  as  (?=ab\K) matches, the reported start of the
-       match can be greater than the end of the match. Using \K in  a  lookbe-
-       hind  assertion at the start of a pattern can also lead to odd effects.
-       For example, consider this pattern:
+       From  version  5.32.0  Perl  forbids the use of \K in lookaround asser-
+       tions. From release 10.38 PCRE2 also forbids this by default.  However,
+       the  PCRE2_EXTRA_ALLOW_LOOKAROUND_BSK  option  can be used when calling
+       pcre2_compile() to re-enable the previous behaviour. When  this  option
+       is set, \K is acted upon when it occurs inside positive assertions, but
+       is ignored in negative assertions. Note that when  a  pattern  such  as
+       (?=ab\K)  matches,  the reported start of the match can be greater than
+       the end of the match. Using \K in a lookbehind assertion at  the  start
+       of  a  pattern can also lead to odd effects. For example, consider this
+       pattern:
 
          (?<=\Kfoo)bar
 
@@ -9621,14 +9632,14 @@ SEE ALSO
 AUTHOR
 
        Philip Hazel
-       University Computing Service
+       Retired from University Computing Service
        Cambridge, England.
 
 
 REVISION
 
-       Last updated: 06 October 2020
-       Copyright (c) 1997-2020 University of Cambridge.
+       Last updated: 30 August 2021
+       Copyright (c) 1997-2021 University of Cambridge.
 ------------------------------------------------------------------------------
  
  
@@ -10735,7 +10746,11 @@ REPORTED MATCH POINT SETTING
 
          \K          set reported start of match
 
-       \K is honoured in positive assertions, but ignored in negative ones.
+       From  release 10.38 \K is not permitted by default in lookaround asser-
+       tions, for compatibility with Perl.  However,  if  the  PCRE2_EXTRA_AL-
+       LOW_LOOKAROUND_BSK option is set, the previous behaviour is re-enabled.
+       When this option is set, \K is honoured in positive assertions, but ig-
+       nored in negative ones.
 
 
 ALTERNATION
@@ -10985,14 +11000,14 @@ SEE ALSO
 AUTHOR
 
        Philip Hazel
-       University Computing Service
+       Retired from University Computing Service
        Cambridge, England.
 
 
 REVISION
 
-       Last updated: 28 December 2019
-       Copyright (c) 1997-2019 University of Cambridge.
+       Last updated: 30 August 2021
+       Copyright (c) 1997-2021 University of Cambridge.
 ------------------------------------------------------------------------------
  
  
diff --git a/doc/pcre2demo.3 b/doc/pcre2demo.3
index 37f5874..a678a68 100644
--- a/doc/pcre2demo.3
+++ b/doc/pcre2demo.3
@@ -234,9 +234,12 @@ pcre2_match_data_create_from_pattern() above. */
 if (rc == 0)
   printf("ovector was not big enough for all the captured substrings\en");
 
-/* We must guard against patterns such as /(?=.\eK)/ that use \eK in an assertion
-to set the start of a match later than its end. In this demonstration program,
-we just detect this case and give up. */
+/* Since release 10.38 PCRE2 has locked out the use of \eK in lookaround 
+assertions. However, there is an option to re-enable the old behaviour. If that 
+is set, it is possible to run patterns such as /(?=.\eK)/ that use \eK in an
+assertion to set the start of a match later than its end. In this demonstration
+program, we show how to detect this case, but it shouldn't arise because the 
+option is never set. */
 
 if (ovector[0] > ovector[1])
   {
diff --git a/doc/pcre2test.txt b/doc/pcre2test.txt
index 561952c..217bed5 100644
--- a/doc/pcre2test.txt
+++ b/doc/pcre2test.txt
@@ -24,17 +24,11 @@ SYNOPSIS
        tion  options, control how the subject is processed, and what output is
        produced.
 
-       As the original fairly simple PCRE library evolved,  it  acquired  many
-       different  features,  and  as  a  result, the original pcretest program
-       ended up with a lot of options in a messy, arcane  syntax  for  testing
-       all the features. The move to the new PCRE2 API provided an opportunity
-       to re-implement the test program as pcre2test, with a cleaner  modifier
-       syntax.  Nevertheless,  there are still many obscure modifiers, some of
-       which are specifically designed for use in conjunction  with  the  test
-       script  and  data  files that are distributed as part of PCRE2. All the
-       modifiers are documented here, some  without  much  justification,  but
-       many  of  them  are  unlikely  to be of use except when testing the li-
-       braries.
+       There are many obscure modifiers, some of which  are  specifically  de-
+       signed  for use in conjunction with the test script and data files that
+       are distributed as part of PCRE2.  All  the  modifiers  are  documented
+       here, some without much justification, but many of them are unlikely to
+       be of use except when testing the libraries.
 
 
 PCRE2's 8-BIT, 16-BIT AND 32-BIT LIBRARIES
@@ -58,10 +52,10 @@ PCRE2's 8-BIT, 16-BIT AND 32-BIT LIBRARIES
 INPUT ENCODING
 
        Input  to  pcre2test is processed line by line, either by calling the C
-       library's fgets() function, or via the  libreadline  library.  In  some
-       Windows  environments  character 26 (hex 1A) causes an immediate end of
-       file, and no further data is read, so this character should be  avoided
-       unless you really want that action.
+       library's fgets() function, or via the libreadline or libedit  library.
+       In  some Windows environments character 26 (hex 1A) causes an immediate
+       end of file, and no further data is read, so this character  should  be
+       avoided unless you really want that action.
 
        The  input  is  processed using using C's string functions, so must not
        contain binary zeros, even though in  Unix-like  environments,  fgets()
@@ -454,11 +448,11 @@ PATTERN SYNTAX
 
 SUBJECT LINE SYNTAX
 
-       Before   each   subject   line   is   passed   to   pcre2_match()    or
-       pcre2_dfa_match(), leading and trailing white space is removed, and the
-       line is scanned for backslash escapes, unless the subject_literal modi-
-       fier was set for the pattern. The following provide a means of encoding
-       non-printing characters in a visible way:
+       Before each subject line is passed to pcre2_match(), pcre2_dfa_match(),
+       or  pcre2_jit_match(), leading and trailing white space is removed, and
+       the line is scanned for backslash escapes, unless  the  subject_literal
+       modifier  was set for the pattern. The following provide a means of en-
+       coding non-printing characters in a visible way:
 
          \a         alarm (BEL, \x07)
          \b         backspace (\x08)
@@ -553,6 +547,7 @@ PATTERN MODIFIERS
        options.
 
              allow_empty_class         set PCRE2_ALLOW_EMPTY_CLASS
+             allow_lookaround_bsk      set PCRE2_EXTRA_ALLOW_LOOKAROUND_BSK
              allow_surrogate_escapes   set PCRE2_EXTRA_ALLOW_SURROGATE_ESCAPES
              alt_bsux                  set PCRE2_ALT_BSUX
              alt_circumflex            set PCRE2_ALT_CIRCUMFLEX
@@ -1938,5 +1933,5 @@ AUTHOR
 
 REVISION
 
-       Last updated: 28 August 2021
+       Last updated: 30 August 2021
        Copyright (c) 1997-2021 University of Cambridge.