Implement Perl's /n option, which is the same as PCRE2_NO_AUTO_CAPTURE.

ChangeLog

@@ -151,6 +151,8 @@ tests to improve coverage.
     
 29. Implemented PCRE2_EXTENDED_MORE and related /xx and (?xx) features. 
 
+30. Implement (?n: for PCRE2_NO_AUTO_CAPTURE, because Perl now has this.
+
 
 Version 10.23 14-February-2017
 ------------------------------

doc/pcre2api.3

@@ -1,4 +1,4 @@
-.TH PCRE2API 3 "17 April 2017" "PCRE2 10.30"
+.TH PCRE2API 3 "18 April 2017" "PCRE2 10.30"
 .SH NAME
 PCRE2 - Perl-compatible regular expressions (revised API)
 .sp
@@ -1426,8 +1426,8 @@ PCRE2_NEVER_UTF causes an error.
 If this option is set, it disables the use of numbered capturing parentheses in
 the pattern. Any opening parenthesis that is not followed by ? behaves as if it
 were followed by ?: but named parentheses can still be used for capturing (and
-they acquire numbers in the usual way). There is no equivalent of this option
+they acquire numbers in the usual way). This is the same as Perl's /n option.
-in Perl. Note that, if this option is set, references to capturing groups (back
+Note that, when this option is set, references to capturing groups (back
 references or recursion/subroutine calls) may only refer to named groups,
 though the reference can be by name or by number.
 .sp
@@ -3402,6 +3402,6 @@ Cambridge, England.
 .rs
 .sp
 .nf
-Last updated: 17 April 2017
+Last updated: 18 April 2017
 Copyright (c) 1997-2017 University of Cambridge.
 .fi

doc/pcre2pattern.3

@@ -1543,12 +1543,13 @@ alternative in the subpattern.
 .rs
 .sp
 The settings of the PCRE2_CASELESS, PCRE2_MULTILINE, PCRE2_DOTALL,
-PCRE2_EXTENDED, and PCRE2_EXTENDED_MORE options (which are Perl-compatible) can
+PCRE2_EXTENDED, PCRE2_EXTENDED_MORE, and PCRE2_NO_AUTO_CAPTURE options (which
-be changed from within the pattern by a sequence of Perl option letters
+are Perl-compatible) can be changed from within the pattern by a sequence of
-enclosed between "(?" and ")". The option letters are
+Perl option letters enclosed between "(?" and ")". The option letters are
 .sp
   i  for PCRE2_CASELESS
   m  for PCRE2_MULTILINE
+  n  for PCRE2_NO_AUTO_CAPTURE 
   s  for PCRE2_DOTALL
   x  for PCRE2_EXTENDED
   xx for PCRE2_EXTENDED_MORE

doc/pcre2syntax.3

@@ -407,6 +407,7 @@ but some of them use Unicode properties if PCRE2_UCP is set. You can use
   (?i)            caseless
   (?J)            allow duplicate names
   (?m)            multiline
+  (?n)            no auto capture 
   (?s)            single line (dotall)
   (?U)            default ungreedy (lazy)
   (?x)            extended: ignore white space except in classes

doc/pcre2test.1

@@ -1,4 +1,4 @@
-.TH PCRE2TEST 1 "17 April 2017" "PCRE 10.30"
+.TH PCRE2TEST 1 "18 April 2017" "PCRE 10.30"
 .SH NAME
 pcre2test - a program for testing Perl-compatible regular expressions.
 .SH SYNOPSIS
@@ -519,10 +519,11 @@ by a previous \fB#pattern\fP command.
 .SS "Setting compilation options"
 .rs
 .sp
-The following modifiers set options for \fBpcre2_compile()\fP. The most common
+The following modifiers set options for \fBpcre2_compile()\fP. There are some
-ones have single-letter abbreviations, with special handling for /x (to make
+single-letter abbreviations that are the same as Perl options. There is special
-it like Perl). If a second x is present, PCRE2_EXTENDED is converted into
+handling for /x: if a second x is present, PCRE2_EXTENDED is converted into
-PCRE2_EXTENDED_MORE. A third appearance adds PCRE2_EXTENDED as well. See
+PCRE2_EXTENDED_MORE as in Perl. A third appearance adds PCRE2_EXTENDED as well, 
+though this makes no difference to the way \fBpcre2_compile()\fP behaves. See
 .\" HREF
 \fBpcre2api\fP
 .\"
@@ -547,7 +548,7 @@ for a description of the effects of these options.
       never_backslash_c         set PCRE2_NEVER_BACKSLASH_C
       never_ucp                 set PCRE2_NEVER_UCP
       never_utf                 set PCRE2_NEVER_UTF
-      no_auto_capture           set PCRE2_NO_AUTO_CAPTURE
+  /n  no_auto_capture           set PCRE2_NO_AUTO_CAPTURE
       no_auto_possess           set PCRE2_NO_AUTO_POSSESS
       no_dotstar_anchor         set PCRE2_NO_DOTSTAR_ANCHOR
       no_start_optimize         set PCRE2_NO_START_OPTIMIZE
@@ -570,7 +571,8 @@ being passed to library functions.
 .rs
 .sp
 The following modifiers affect the compilation process or request information
-about the pattern:
+about the pattern. There are single-letter abbreviations for some that are
+heavily used in the test files.
 .sp
       bsr=[anycrlf|unicode]     specify \eR handling
   /B  bincode                   show binary code without lengths
@@ -1786,6 +1788,6 @@ Cambridge, England.
 .rs
 .sp
 .nf
-Last updated: 17 April 2017
+Last updated: 18 April 2017
 Copyright (c) 1997-2017 University of Cambridge.
 .fi

src/pcre2_compile.c

@@ -2233,11 +2233,11 @@ typedef struct nest_save {
 #define NSF_RESET          0x0001u
 #define NSF_CONDASSERT     0x0002u
 
-/* These options (changeable within the pattern) are tracked during parsing.
+/* Of the options that are changeable within the pattern, these are tracked
-The rest are put into META_OPTIONS items and used when compiling. */
+during parsing. The rest are used from META_OPTIONS items when compiling. */
 
 #define PARSE_TRACKED_OPTIONS \
-  (PCRE2_EXTENDED|PCRE2_EXTENDED_MORE|PCRE2_DUPNAMES)
+  (PCRE2_DUPNAMES|PCRE2_EXTENDED|PCRE2_EXTENDED_MORE|PCRE2_NO_AUTO_CAPTURE)
 
 /* States used for analyzing ranges in character classes. The two OK values
 must be last. */
@@ -3422,9 +3422,7 @@ while (ptr < ptrend)
         ptr++;
         }
 
-      /* Scan for options imsxJU. Some of them are tracked during parsing (see 
+      /* Scan for options imnsxJU to be set or unset. */
-      PARSE_TRACKED_OPTIONS) as they are local to groups. Others are not needed 
-      till compile time. */ 
 
       else
         {
@@ -3447,6 +3445,7 @@ while (ptr < ptrend)
 
             case CHAR_i: *optset |= PCRE2_CASELESS; break;
             case CHAR_m: *optset |= PCRE2_MULTILINE; break;
+            case CHAR_n: *optset |= PCRE2_NO_AUTO_CAPTURE; break;
             case CHAR_s: *optset |= PCRE2_DOTALL; break;
             case CHAR_U: *optset |= PCRE2_UNGREEDY; break;
             

src/pcre2test.c

@@ -720,13 +720,14 @@ typedef struct c1modstruct {
 } c1modstruct;
 
 static c1modstruct c1modlist[] = {
-  { "bincode",      'B',           -1 },
+  { "bincode",         'B',           -1 },
-  { "info",         'I',           -1 },
+  { "info",            'I',           -1 },
-  { "global",       'g',           -1 },
+  { "global",          'g',           -1 },
-  { "caseless",     'i',           -1 },
+  { "caseless",        'i',           -1 },
-  { "multiline",    'm',           -1 },
+  { "multiline",       'm',           -1 },
-  { "dotall",       's',           -1 },
+  { "no_auto_capture", 'n',           -1 },
-  { "extended",     'x',           -1 }
+  { "dotall",          's',           -1 },
+  { "extended",        'x',           -1 }
 };
 
 #define C1MODLISTCOUNT sizeof(c1modlist)/sizeof(c1modstruct)

testdata/testinput2

@@ -5259,4 +5259,6 @@ a)"xI
 
 /[a b](?xx: [ 12 ] (?-x:[ 34 ]) )y z/B
 
+/(a)(?-n:(b))(c)/nB
+
 # End of testinput2 

testdata/testoutput2

@@ -15945,6 +15945,24 @@ Subject length lower bound = 1
         End
 ------------------------------------------------------------------
 
+/(a)(?-n:(b))(c)/nB
+------------------------------------------------------------------
+        Bra
+        Bra
+        a
+        Ket
+        Bra
+        CBra 1
+        b
+        Ket
+        Ket
+        Bra
+        c
+        Ket
+        Ket
+        End
+------------------------------------------------------------------
+
 # End of testinput2 
 Error -64: PCRE2_ERROR_BADDATA (unknown error number)
 Error -62: bad serialized data