pcre/testdata/testinput2

/-- This set of tests is not Perl-compatible. It checks on special features
    of PCRE's API, error diagnostics, and the compiled code of some patterns.
    It also checks the non-Perl syntax the PCRE supports (Python, .NET, 
    Oniguruma). Finally, there are some tests where PCRE and Perl differ, 
    either because PCRE can't be compatible, or there is a possible Perl 
    bug.
    
    NOTE: This is a non-UTF set of tests. When UTF support is needed, use
    test 5, and if Unicode Property Support is needed, use test 7. --/
    
< forbid 8W 
  
/(a)b|/I

/abc/I
    abc
    defabc
    \Aabc
    *** Failers
    \Adefabc
    ABC

/^abc/I
    abc
    \Aabc
    *** Failers
    defabc
    \Adefabc

/a+bc/I

/a*bc/I

/a{3}bc/I

/(abc|a+z)/I

/^abc$/I
    abc
    *** Failers
    def\nabc

/ab\idef/X

/(?X)ab\idef/X

/x{5,4}/

/z{65536}/

/[abcd/

/(?X)[\B]/

/(?X)[\R]/

/(?X)[\X]/

/[\B]/BZ

/[\R]/BZ

/[\X]/BZ

/[z-a]/

/^*/

/(abc/

/(?# abc/

/(?z)abc/

/.*b/I

/.*?b/I

/cat|dog|elephant/I
    this sentence eventually mentions a cat
    this sentences rambles on and on for a while and then reaches elephant

/cat|dog|elephant/IS
    this sentence eventually mentions a cat
    this sentences rambles on and on for a while and then reaches elephant

/cat|dog|elephant/IiS
    this sentence eventually mentions a CAT cat
    this sentences rambles on and on for a while to elephant ElePhant

/a|[bcd]/IS

/(a|[^\dZ])/IS

/(a|b)*[\s]/IS

/(ab\2)/

/{4,5}abc/

/(a)(b)(c)\2/I
    abcb
    \O0abcb
    \O3abcb
    \O6abcb
    \O9abcb
    \O12abcb

/(a)bc|(a)(b)\2/I
    abc
    \O0abc
    \O3abc
    \O6abc
    aba
    \O0aba
    \O3aba
    \O6aba
    \O9aba
    \O12aba

/abc$/IE
    abc
    *** Failers
    abc\n
    abc\ndef

/(a)(b)(c)(d)(e)\6/

/the quick brown fox/I
    the quick brown fox
    this is a line with the quick brown fox

/the quick brown fox/IA
    the quick brown fox
    *** Failers
    this is a line with the quick brown fox

/ab(?z)cd/

/^abc|def/I
    abcdef
    abcdef\B

/.*((abc)$|(def))/I
    defabc
    \Zdefabc

/)/

/a[]b/

/[^aeiou ]{3,}/I
    co-processors, and for

/<.*>/I
    abc<def>ghi<klm>nop

/<.*?>/I
    abc<def>ghi<klm>nop

/<.*>/IU
    abc<def>ghi<klm>nop

/(?U)<.*>/I
    abc<def>ghi<klm>nop

/<.*?>/IU
    abc<def>ghi<klm>nop

/={3,}/IU
    abc========def

/(?U)={3,}?/I
    abc========def

/(?<!bar|cattle)foo/I
    foo
    catfoo
    *** Failers
    the barfoo
    and cattlefoo

/(?<=a+)b/

/(?<=aaa|b{0,3})b/

/(?<!(foo)a\1)bar/

/(?i)abc/I

/(a|(?m)a)/I

/(?i)^1234/I

/(^b|(?i)^d)/I

/(?s).*/I

/[abcd]/IS

/(?i)[abcd]/IS

/(?m)[xy]|(b|c)/IS

/(^a|^b)/Im

/(?i)(^a|^b)/Im

/(a)(?(1)a|b|c)/

/(?(?=a)a|b|c)/

/(?(1a)/

/(?(1a))/

/(?(?i))/

/(?(abc))/

/(?(?<ab))/

/((?s)blah)\s+\1/I

/((?i)blah)\s+\1/I

/((?i)b)/IDZS

/(a*b|(?i:c*(?-i)d))/IS

/a$/I
    a
    a\n
    *** Failers
    \Za
    \Za\n

/a$/Im
    a
    a\n
    \Za\n
    *** Failers
    \Za

/\Aabc/Im

/^abc/Im

/^((a+)(?U)([ab]+)(?-U)([bc]+)(\w*))/I
  aaaaabbbbbcccccdef

/(?<=foo)[ab]/IS

/(?<!foo)(alpha|omega)/IS

/(?!alphabet)[ab]/IS

/(?<=foo\n)^bar/Im
    foo\nbarbar
    ***Failers
    rhubarb
    barbell
    abc\nbarton

/^(?<=foo\n)bar/Im
    foo\nbarbar
    ***Failers
    rhubarb
    barbell
    abc\nbarton

/(?>^abc)/Im
    abc
    def\nabc
    *** Failers
    defabc

/(?<=ab(c+)d)ef/

/(?<=ab(?<=c+)d)ef/

/(?<=ab(c|de)f)g/

/The next three are in testinput2 because they have variable length branches/

/(?<=bullock|donkey)-cart/I
    the bullock-cart
    a donkey-cart race
    *** Failers
    cart
    horse-and-cart

/(?<=ab(?i)x|y|z)/I

/(?>.*)(?<=(abcd)|(xyz))/I
    alphabetabcd
    endingxyz

/(?<=ab(?i)x(?-i)y|(?i)z|b)ZZ/I
    abxyZZ
    abXyZZ
    ZZZ
    zZZ
    bZZ
    BZZ
    *** Failers
    ZZ
    abXYZZ
    zzz
    bzz

/(?<!(foo)a)bar/I
    bar
    foobbar
    *** Failers
    fooabar

/This one is here because Perl behaves differently; see also the following/I

/^(a\1?){4}$/I
    aaaa
    aaaaaa
    
/Perl does not fail these two for the final subjects. Neither did PCRE until/
/release 8.01. The problem is in backtracking into a subpattern that contains/
/a recursive reference to itself. PCRE has now made these into atomic patterns./

/^(xa|=?\1a){2}$/
    xa=xaa
    ** Failers
    xa=xaaa

/^(xa|=?\1a)+$/
    xa=xaa
    ** Failers
    xa=xaaa

/These are syntax tests from Perl 5.005/I

/a[b-a]/

/a[]b/

/a[/

/*a/

/(*)b/

/abc)/

/(abc/

/a**/

/)(/

/\1/

/\2/

/(a)|\2/

/a[b-a]/Ii

/a[]b/Ii

/a[/Ii

/*a/Ii

/(*)b/Ii

/abc)/Ii

/(abc/Ii

/a**/Ii

/)(/Ii

/:(?:/

/(?<%)b/

/a(?{)b/

/a(?{{})b/

/a(?{}})b/

/a(?{"{"})b/

/a(?{"{"}})b/

/(?(1?)a|b)/

/[a[:xyz:/

/(?<=x+)y/

/a{37,17}/

/abc/\

/abc/\i

/(a)bc(d)/I
    abcd
    abcd\C2
    abcd\C5

/(.{20})/I
    abcdefghijklmnopqrstuvwxyz
    abcdefghijklmnopqrstuvwxyz\C1
    abcdefghijklmnopqrstuvwxyz\G1

/(.{15})/I
    abcdefghijklmnopqrstuvwxyz
    abcdefghijklmnopqrstuvwxyz\C1\G1

/(.{16})/I
    abcdefghijklmnopqrstuvwxyz
    abcdefghijklmnopqrstuvwxyz\C1\G1\L

/^(a|(bc))de(f)/I
    adef\G1\G2\G3\G4\L
    bcdef\G1\G2\G3\G4\L
    adefghijk\C0

/^abc\00def/I
    abc\00def\L\C0

/word ((?:[a-zA-Z0-9]+ )((?:[a-zA-Z0-9]+ )((?:[a-zA-Z0-9]+ )((?:[a-zA-Z0-9]+
)((?:[a-zA-Z0-9]+ )((?:[a-zA-Z0-9]+ )((?:[a-zA-Z0-9]+ )((?:[a-zA-Z0-9]+
)?)?)?)?)?)?)?)?)?otherword/I

/.*X/IDZ

/.*X/IDZs

/(.*X|^B)/IDZ

/(.*X|^B)/IDZs

/(?s)(.*X|^B)/IDZ

/(?s:.*X|^B)/IDZ

/\Biss\B/I+
    Mississippi

/iss/IG+
    Mississippi

/\Biss\B/IG+
    Mississippi

/\Biss\B/Ig+
    Mississippi
    *** Failers
    Mississippi\A

/(?<=[Ms])iss/Ig+
    Mississippi

/(?<=[Ms])iss/IG+
    Mississippi

/^iss/Ig+
    ississippi

/.*iss/Ig+
    abciss\nxyzisspqr

/.i./I+g
    Mississippi
    Mississippi\A
    Missouri river
    Missouri river\A

/^.is/I+g
    Mississippi

/^ab\n/Ig+
    ab\nab\ncd

/^ab\n/Img+
    ab\nab\ncd

/abc/I

/abc|bac/I

/(abc|bac)/I

/(abc|(c|dc))/I

/(abc|(d|de)c)/I

/a*/I

/a+/I

/(baa|a+)/I

/a{0,3}/I

/baa{3,}/I

/"([^\\"]+|\\.)*"/I

/(abc|ab[cd])/I

/(a|.)/I

/a|ba|\w/I

/abc(?=pqr)/I

/...(?<=abc)/I

/abc(?!pqr)/I

/ab./I

/ab[xyz]/I

/abc*/I

/ab.c*/I

/a.c*/I

/.c*/I

/ac*/I

/(a.c*|b.c*)/I

/a.c*|aba/I

/.+a/I

/(?=abcda)a.*/I

/(?=a)a.*/I

/a(b)*/I

/a\d*/I

/ab\d*/I

/a(\d)*/I

/abcde{0,0}/I

/ab\d+/I

/a(?(1)b)(.)/I

/a(?(1)bag|big)(.)/I

/a(?(1)bag|big)*(.)/I

/a(?(1)bag|big)+(.)/I

/a(?(1)b..|b..)(.)/I

/ab\d{0}e/I

/a?b?/I
    a
    b
    ab
    \
    *** Failers
    \N

/|-/I
    abcd
    -abc
    \Nab-c
    *** Failers
    \Nabc

/^.?abcd/IS

/\(             # ( at start
  (?:           # Non-capturing bracket
  (?>[^()]+)    # Either a sequence of non-brackets (no backtracking)
  |             # Or
  (?R)          # Recurse - i.e. nested bracketed string
  )*            # Zero or more contents
  \)            # Closing )
  /Ix
    (abcd)
    (abcd)xyz
    xyz(abcd)
    (ab(xy)cd)pqr
    (ab(xycd)pqr
    () abc ()
    12(abcde(fsh)xyz(foo(bar))lmno)89
    *** Failers
    abcd
    abcd)
    (abcd

/\(  ( (?>[^()]+) | (?R) )* \) /Ixg
    (ab(xy)cd)pqr
    1(abcd)(x(y)z)pqr

/\(  (?: (?>[^()]+) | (?R) ) \) /Ix
    (abcd)
    (ab(xy)cd)
    (a(b(c)d)e)
    ((ab))
    *** Failers
    ()

/\(  (?: (?>[^()]+) | (?R) )? \) /Ix
    ()
    12(abcde(fsh)xyz(foo(bar))lmno)89

/\(  ( (?>[^()]+) | (?R) )* \) /Ix
    (ab(xy)cd)

/\( ( ( (?>[^()]+) | (?R) )* ) \) /Ix
    (ab(xy)cd)

/\( (123)? ( ( (?>[^()]+) | (?R) )* ) \) /Ix
    (ab(xy)cd)
    (123ab(xy)cd)

/\( ( (123)? ( (?>[^()]+) | (?R) )* ) \) /Ix
    (ab(xy)cd)
    (123ab(xy)cd)

/\( (((((((((( ( (?>[^()]+) | (?R) )* )))))))))) \) /Ix
    (ab(xy)cd)

/\( ( ( (?>[^()<>]+) | ((?>[^()]+)) | (?R) )* ) \) /Ix
    (abcd(xyz<p>qrs)123)

/\( ( ( (?>[^()]+) | ((?R)) )* ) \) /Ix
    (ab(cd)ef)
    (ab(cd(ef)gh)ij)

/^[[:alnum:]]/DZ

/^[[:^alnum:]]/DZ

/^[[:alpha:]]/DZ

/^[[:^alpha:]]/DZ

/[_[:alpha:]]/IS

/^[[:ascii:]]/DZ

/^[[:^ascii:]]/DZ

/^[[:blank:]]/DZ

/^[[:^blank:]]/DZ

/[\n\x0b\x0c\x0d[:blank:]]/IS

/^[[:cntrl:]]/DZ

/^[[:digit:]]/DZ

/^[[:graph:]]/DZ

/^[[:lower:]]/DZ

/^[[:print:]]/DZ

/^[[:punct:]]/DZ

/^[[:space:]]/DZ

/^[[:upper:]]/DZ

/^[[:xdigit:]]/DZ

/^[[:word:]]/DZ

/^[[:^cntrl:]]/DZ

/^[12[:^digit:]]/DZ

/^[[:^blank:]]/DZ

/[01[:alpha:]%]/DZ

/[[.ch.]]/I

/[[=ch=]]/I

/[[:rhubarb:]]/I

/[[:upper:]]/Ii
    A
    a

/[[:lower:]]/Ii
    A
    a

/((?-i)[[:lower:]])[[:lower:]]/Ii
    ab
    aB
    *** Failers
    Ab
    AB

/[\200-\110]/I

/^(?(0)f|b)oo/I

/This one's here because of the large output vector needed/I

/(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\d+(?:\s|$))(\w+)\s+(\270)/I
    \O900 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 ABC ABC

/This one's here because Perl does this differently and PCRE can't at present/I

/(main(O)?)+/I
    mainmain
    mainOmain

/These are all cases where Perl does it differently (nested captures)/I

/^(a(b)?)+$/I
    aba

/^(aa(bb)?)+$/I
    aabbaa

/^(aa|aa(bb))+$/I
    aabbaa

/^(aa(bb)??)+$/I
    aabbaa

/^(?:aa(bb)?)+$/I
    aabbaa

/^(aa(b(b))?)+$/I
    aabbaa

/^(?:aa(b(b))?)+$/I
    aabbaa

/^(?:aa(b(?:b))?)+$/I
    aabbaa

/^(?:aa(bb(?:b))?)+$/I
    aabbbaa

/^(?:aa(b(?:bb))?)+$/I
    aabbbaa

/^(?:aa(?:b(b))?)+$/I
    aabbaa

/^(?:aa(?:b(bb))?)+$/I
    aabbbaa

/^(aa(b(bb))?)+$/I
    aabbbaa

/^(aa(bb(bb))?)+$/I
    aabbbbaa

/--------------------------------------------------------------------/I

/#/IxDZ

/a#/IxDZ

/[\s]/DZ

/[\S]/DZ

/a(?i)b/DZ
    ab
    aB
    *** Failers
    AB

/(a(?i)b)/DZ
    ab
    aB
    *** Failers
    AB

/   (?i)abc/IxDZ

/#this is a comment
  (?i)abc/IxDZ

/123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890/DZ

/\Q123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890/DZ

/\Q\E/DZ
    \

/\Q\Ex/DZ

/ \Q\E/DZ

/a\Q\E/DZ
  abc
  bca
  bac

/a\Q\Eb/DZ
  abc

/\Q\Eabc/DZ

/x*+\w/DZ
    *** Failers
    xxxxx

/x?+/DZ

/x++/DZ

/x{1,3}+/BZO

/x{1,3}+/BZOi

/[^x]{1,3}+/BZO

/[^x]{1,3}+/BZOi

/(x)*+/DZ

/^(\w++|\s++)*$/I
    now is the time for all good men to come to the aid of the party
    *** Failers
    this is not a line with only words and spaces!

/(\d++)(\w)/I
    12345a
    *** Failers
    12345+

/a++b/I
    aaab

/(a++b)/I
    aaab

/(a++)b/I
    aaab

/([^()]++|\([^()]*\))+/I
    ((abc(ade)ufh()()x

/\(([^()]++|\([^()]+\))+\)/I
    (abc)
    (abc(def)xyz)
    *** Failers
    ((()aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa

/(abc){1,3}+/DZ

/a+?+/I

/a{2,3}?+b/I

/(?U)a+?+/I

/a{2,3}?+b/IU

/x(?U)a++b/DZ
    xaaaab

/(?U)xa++b/DZ
    xaaaab

/^((a+)(?U)([ab]+)(?-U)([bc]+)(\w*))/DZ

/^x(?U)a+b/DZ

/^x(?U)(a+)b/DZ

/[.x.]/I

/[=x=]/I

/[:x:]/I

/\l/I

/\L/I

/\N{name}/I

/\u/I

/\U/I

/a{1,3}b/U
    ab

/[/I

/[a-/I

/[[:space:]/I

/[\s]/IDZ

/[[:space:]]/IDZ

/[[:space:]abcde]/IDZ

/< (?: (?(R) \d++  | [^<>]*+) | (?R)) * >/Ix
    <>
    <abcd>
    <abc <123> hij>
    <abc <def> hij>
    <abc<>def>
    <abc<>
    *** Failers
    <abc

|8J\$WE\<\.rX\+ix\[d1b\!H\#\?vV0vrK\:ZH1\=2M\>iV\;\?aPhFB\<\*vW\@QW\@sO9\}cfZA\-i\'w\%hKd6gt1UJP\,15_\#QY\$M\^Mss_U\/\]\&LK9\[5vQub\^w\[KDD\<EjmhUZ\?\.akp2dF\>qmj\;2\}YWFdYx\.Ap\]hjCPTP\(n28k\+3\;o\&WXqs\/gOXdr\$\:r\'do0\;b4c\(f_Gr\=\"\\4\)\[01T7ajQJvL\$W\~mL_sS\/4h\:x\*\[ZN\=KLs\&L5zX\/\/\>it\,o\:aU\(\;Z\>pW\&T7oP\'2K\^E\:x9\'c\[\%z\-\,64JQ5AeH_G\#KijUKghQw\^\\vea3a\?kka_G\$8\#\`\*kynsxzBLru\'\]k_\[7FrVx\}\^\=\$blx\>s\-N\%j\;D\*aZDnsw\:YKZ\%Q\.Kne9\#hP\?\+b3\(SOvL\,\^\;\&u5\@\?5C5Bhb\=m\-vEh_L15Jl\]U\)0RP6\{q\%L\^_z5E\'Dw6X\b|IDZ

|\$\<\.X\+ix\[d1b\!H\#\?vV0vrK\:ZH1\=2M\>iV\;\?aPhFB\<\*vW\@QW\@sO9\}cfZA\-i\'w\%hKd6gt1UJP\,15_\#QY\$M\^Mss_U\/\]\&LK9\[5vQub\^w\[KDD\<EjmhUZ\?\.akp2dF\>qmj\;2\}YWFdYx\.Ap\]hjCPTP\(n28k\+3\;o\&WXqs\/gOXdr\$\:r\'do0\;b4c\(f_Gr\=\"\\4\)\[01T7ajQJvL\$W\~mL_sS\/4h\:x\*\[ZN\=KLs\&L5zX\/\/\>it\,o\:aU\(\;Z\>pW\&T7oP\'2K\^E\:x9\'c\[\%z\-\,64JQ5AeH_G\#KijUKghQw\^\\vea3a\?kka_G\$8\#\`\*kynsxzBLru\'\]k_\[7FrVx\}\^\=\$blx\>s\-N\%j\;D\*aZDnsw\:YKZ\%Q\.Kne9\#hP\?\+b3\(SOvL\,\^\;\&u5\@\?5C5Bhb\=m\-vEh_L15Jl\]U\)0RP6\{q\%L\^_z5E\'Dw6X\b|IDZ

/(.*)\d+\1/I

/(.*)\d+/I

/(.*)\d+\1/Is

/(.*)\d+/Is

/(.*(xyz))\d+\2/I

/((.*))\d+\1/I
    abc123bc

/a[b]/I

/(?=a).*/I

/(?=abc).xyz/IiI

/(?=abc)(?i).xyz/I

/(?=a)(?=b)/I

/(?=.)a/I

/((?=abcda)a)/I

/((?=abcda)ab)/I

/()a/I

/(?(1)ab|ac)(.)/I

/(?(1)abz|acz)(.)/I

/(?(1)abz)(.)/I

/(?(1)abz)(1)23/I

/(a)+/I

/(a){2,3}/I

/(a)*/I

/[a]/I

/[ab]/I

/[ab]/IS

/[^a]/I

/\d456/I

/\d456/IS

/a^b/I

/^a/Im
  abcde
  xy\nabc
  *** Failers
  xyabc

/c|abc/I

/(?i)[ab]/IS

/[ab](?i)cd/IS

/abc(?C)def/I
    abcdef
    1234abcdef
    *** Failers
    abcxyz
    abcxyzf

/abc(?C)de(?C1)f/I
    123abcdef

/(?C1)\dabc(?C2)def/IS
    1234abcdef
    *** Failers
    abcdef

/(?C1)\dabc(?C2)def/ISS
    1234abcdef
    *** Failers
    abcdef

/(?C255)ab/I

/(?C256)ab/I

/(?Cab)xx/I

/(?C12vr)x/I

/abc(?C)def/I
    *** Failers
    \x83\x0\x61bcdef

/(abc)(?C)de(?C1)f/I
    123abcdef
    123abcdef\C+
    123abcdef\C-
    *** Failers
    123abcdef\C!1

/(?C0)(abc(?C1))*/I
    abcabcabc
    abcabc\C!1!3
    *** Failers
    abcabcabc\C!1!3

/(\d{3}(?C))*/I
    123\C+
    123456\C+
    123456789\C+

/((xyz)(?C)p|(?C1)xyzabc)/I
    xyzabc\C+

/(X)((xyz)(?C)p|(?C1)xyzabc)/I
    Xxyzabc\C+

/(?=(abc))(?C)abcdef/I
    abcdef\C+

/(?!(abc)(?C1)d)(?C2)abcxyz/I
    abcxyz\C+

/(?<=(abc)(?C))xyz/I
   abcxyz\C+

/a(b+)(c*)(?C1)/I
    abbbbbccc\C*1

/a(b+?)(c*?)(?C1)/I
    abbbbbccc\C*1

/(?C)abc/I

/(?C)^abc/I

/(?C)a|b/IS

/(?R)/I

/(a|(?R))/I

/(ab|(bc|(de|(?R))))/I

/x(ab|(bc|(de|(?R))))/I
    xab
    xbc
    xde
    xxab
    xxxab
    *** Failers
    xyab

/(ab|(bc|(de|(?1))))/I

/x(ab|(bc|(de|(?1)x)x)x)/I

/^([^()]|\((?1)*\))*$/I
    abc
    a(b)c
    a(b(c))d
    *** Failers)
    a(b(c)d

/^>abc>([^()]|\((?1)*\))*<xyz<$/I
   >abc>123<xyz<
   >abc>1(2)3<xyz<
   >abc>(1(2)3)<xyz<

/(a(?1)b)/DZ

/(a(?1)+b)/DZ

/^(\d+|\((?1)([+*-])(?1)\)|-(?1))$/I
    12
    (((2+2)*-3)-7)
    -12
    *** Failers
    ((2+2)*-3)-7)

/^(x(y|(?1){2})z)/I
    xyz
    xxyzxyzz
    *** Failers
    xxyzz
    xxyzxyzxyzz

/((< (?: (?(R) \d++  | [^<>]*+) | (?2)) * >))/Ix
    <>
    <abcd>
    <abc <123> hij>
    <abc <def> hij>
    <abc<>def>
    <abc<>
    *** Failers
    <abc

/(?1)/I

/((?2)(abc)/I

/^(abc)def(?1)/I
    abcdefabc

/^(a|b|c)=(?1)+/I
    a=a
    a=b
    a=bc

/^(a|b|c)=((?1))+/I
    a=a
    a=b
    a=bc

/a(?P<name1>b|c)d(?P<longername2>e)/DZ
    abde
    acde

/(?:a(?P<c>c(?P<d>d)))(?P<a>a)/DZ

/(?P<a>a)...(?P=a)bbb(?P>a)d/DZ

/^\W*(?:(?P<one>(?P<two>.)\W*(?P>one)\W*(?P=two)|)|(?P<three>(?P<four>.)\W*(?P>three)\W*(?P=four)|\W*.\W*))\W*$/Ii
    1221
    Satan, oscillate my metallic sonatas!
    A man, a plan, a canal: Panama!
    Able was I ere I saw Elba.
    *** Failers
    The quick brown fox

/((?(R)a|b))\1(?1)?/I
  bb
  bbaa

/(.*)a/Is

/(.*)a\1/Is

/(.*)a(b)\2/Is

/((.*)a|(.*)b)z/Is

/((.*)a|(.*)b)z\1/Is

/((.*)a|(.*)b)z\2/Is

/((.*)a|(.*)b)z\3/Is

/((.*)a|^(.*)b)z\3/Is

/(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)a/Is

/(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)a\31/Is

/(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)|(.*)a\32/Is

/(a)(bc)/INDZ
  abc

/(?P<one>a)(bc)/INDZ
  abc

/(a)(?P<named>bc)/INDZ

/(a+)*zz/I
  aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaazzbbbbbb\M
  aaaaaaaaaaaaaz\M

/(aaa(?C1)bbb|ab)/I
   aaabbb
   aaabbb\C*0
   aaabbb\C*1
   aaabbb\C*-1

/ab(?P<one>cd)ef(?P<two>gh)/I
    abcdefgh
    abcdefgh\C1\Gtwo
    abcdefgh\Cone\Ctwo
    abcdefgh\Cthree

/(?P<Tes>)(?P<Test>)/DZ

/(?P<Test>)(?P<Tes>)/DZ

/(?P<Z>zz)(?P<A>aa)/I
    zzaa\CZ
    zzaa\CA

/(?P<x>eks)(?P<x>eccs)/I

/(?P<abc>abc(?P<def>def)(?P<abc>xyz))/I

"\[((?P<elem>\d+)(,(?P>elem))*)\]"I
    [10,20,30,5,5,4,4,2,43,23,4234]
    *** Failers
    []

"\[((?P<elem>\d+)(,(?P>elem))*)?\]"I
    [10,20,30,5,5,4,4,2,43,23,4234]
    []

/(a(b(?2)c))?/DZ

/(a(b(?2)c))*/DZ

/(a(b(?2)c)){0,2}/DZ

/[ab]{1}+/DZ

/((w\/|-|with)*(free|immediate)*.*?shipping\s*[!.-]*)/Ii
     Baby Bjorn Active Carrier - With free SHIPPING!!

/((w\/|-|with)*(free|immediate)*.*?shipping\s*[!.-]*)/IiS
     Baby Bjorn Active Carrier - With free SHIPPING!!

/a*.*b/ISDZ

/(a|b)*.?c/ISDZ

/abc(?C255)de(?C)f/DZ

/abcde/ICDZ
  abcde
  abcdfe

/a*b/ICDZS
  ab
  aaaab
  aaaacb

/a*b/ICDZSS
  ab
  aaaab
  aaaacb

/a+b/ICDZ
  ab
  aaaab
  aaaacb

/(abc|def)x/ICDZS
  abcx
  defx
  ** Failers 
  abcdefzx

/(abc|def)x/ICDZSS
  abcx
  defx
  ** Failers 
  abcdefzx

/(ab|cd){3,4}/IC
  ababab
  abcdabcd
  abcdcdcdcdcd

/([ab]{,4}c|xy)/ICDZS
    Note: that { does NOT introduce a quantifier

/([ab]{,4}c|xy)/ICDZSS
    Note: that { does NOT introduce a quantifier

/([ab]{1,4}c|xy){4,5}?123/ICDZ
    aacaacaacaacaac123

/\b.*/I
  ab cd\>1

/\b.*/Is
  ab cd\>1

/(?!.bcd).*/I
  Xbcd12345

/abcde/I
    ab\P
    abc\P
    abcd\P
    abcde\P
    the quick brown abc\P
    ** Failers\P
    the quick brown abxyz fox\P

"^(0?[1-9]|[12][0-9]|3[01])/(0?[1-9]|1[012])/(20)?\d\d$"I
    13/05/04\P
    13/5/2004\P
    02/05/09\P
    1\P
    1/2\P
    1/2/0\P
    1/2/04\P
    0\P
    02/\P
    02/0\P
    02/1\P
    ** Failers\P
    \P
    123\P
    33/4/04\P
    3/13/04\P
    0/1/2003\P
    0/\P
    02/0/\P
    02/13\P

/0{0,2}ABC/I

/\d{3,}ABC/I

/\d*ABC/I

/[abc]+DE/I

/[abc]?123/I
    123\P
    a\P
    b\P
    c\P
    c12\P
    c123\P

/^(?:\d){3,5}X/I
    1\P
    123\P
    123X
    1234\P
    1234X
    12345\P
    12345X
    *** Failers
    1X
    123456\P

//S-KF>testsavedregex

/abc/IS>testsavedregex
<testsavedregex
    abc
    ** Failers
    bca

/abc/ISS>testsavedregex
<testsavedregex
    abc
    ** Failers
    bca

/abc/IFS>testsavedregex
<testsavedregex
    abc
    ** Failers
    bca

/abc/IFSS>testsavedregex
<testsavedregex
    abc
    ** Failers
    bca

/(a|b)/IS>testsavedregex
<testsavedregex
    abc
    ** Failers
    def

/(a|b)/ISS>testsavedregex
<testsavedregex
    abc
    ** Failers
    def

/(a|b)/ISF>testsavedregex
<testsavedregex
    abc
    ** Failers
    def

/(a|b)/ISSF>testsavedregex
<testsavedregex
    abc
    ** Failers
    def

~<(\w+)/?>(.)*</(\1)>~smgI
    \J1024<!DOCTYPE seite SYSTEM "http://www.lco.lineas.de/xmlCms.dtd">\n<seite>\n<dokumenteninformation>\n<seitentitel>Partner der LCO</seitentitel>\n<sprache>de</sprache>\n<seitenbeschreibung>Partner der LINEAS Consulting\nGmbH</seitenbeschreibung>\n<schluesselworte>LINEAS Consulting GmbH Hamburg\nPartnerfirmen</schluesselworte>\n<revisit>30 days</revisit>\n<robots>index,follow</robots>\n<menueinformation>\n<aktiv>ja</aktiv>\n<menueposition>3</menueposition>\n<menuetext>Partner</menuetext>\n</menueinformation>\n<lastedited>\n<autor>LCO</autor>\n<firma>LINEAS Consulting</firma>\n<datum>15.10.2003</datum>\n</lastedited>\n</dokumenteninformation>\n<inhalt>\n\n<absatzueberschrift>Die Partnerfirmen der LINEAS Consulting\nGmbH</absatzueberschrift>\n\n<absatz><link ziel="http://www.ca.com/" zielfenster="_blank">\n<bild name="logo_ca.gif" rahmen="no"/></link> <link\nziel="http://www.ey.com/" zielfenster="_blank"><bild\nname="logo_euy.gif" rahmen="no"/></link>\n</absatz>\n\n<absatz><link ziel="http://www.cisco.de/" zielfenster="_blank">\n<bild name="logo_cisco.gif" rahmen="ja"/></link></absatz>\n\n<absatz><link ziel="http://www.atelion.de/"\nzielfenster="_blank"><bild\nname="logo_atelion.gif" rahmen="no"/></link>\n</absatz>\n\n<absatz><link ziel="http://www.line-information.de/"\nzielfenster="_blank">\n<bild name="logo_line_information.gif" rahmen="no"/></link>\n</absatz>\n\n<absatz><bild name="logo_aw.gif" rahmen="no"/></absatz>\n\n<absatz><link ziel="http://www.incognis.de/"\nzielfenster="_blank"><bild\nname="logo_incognis.gif" rahmen="no"/></link></absatz>\n\n<absatz><link ziel="http://www.addcraft.com/"\nzielfenster="_blank"><bild\nname="logo_addcraft.gif" rahmen="no"/></link></absatz>\n\n<absatz><link ziel="http://www.comendo.com/"\nzielfenster="_blank"><bild\nname="logo_comendo.gif" rahmen="no"/></link></absatz>\n\n</inhalt>\n</seite>

/^a/IF

/line\nbreak/I
    this is a line\nbreak
    line one\nthis is a line\nbreak in the second line

/line\nbreak/If
    this is a line\nbreak
    ** Failers
    line one\nthis is a line\nbreak in the second line

/line\nbreak/Imf
    this is a line\nbreak
    ** Failers
    line one\nthis is a line\nbreak in the second line

/(?i)(?-i)AbCd/I
    AbCd
    ** Failers
    abcd

/a{11111111111111111111}/I

/(){64294967295}/I

/(){2,4294967295}/I

"(?i:a)(?i:b)(?i:c)(?i:d)(?i:e)(?i:f)(?i:g)(?i:h)(?i:i)(?i:j)(k)(?i:l)A\1B"I
    abcdefghijklAkB

"(?P<n0>a)(?P<n1>b)(?P<n2>c)(?P<n3>d)(?P<n4>e)(?P<n5>f)(?P<n6>g)(?P<n7>h)(?P<n8>i)(?P<n9>j)(?P<n10>k)(?P<n11>l)A\11B"I
    abcdefghijklAkB

"(a)(b)(c)(d)(e)(f)(g)(h)(i)(j)(k)(l)A\11B"I
    abcdefghijklAkB

"(?P<name0>a)(?P<name1>a)(?P<name2>a)(?P<name3>a)(?P<name4>a)(?P<name5>a)(?P<name6>a)(?P<name7>a)(?P<name8>a)(?P<name9>a)(?P<name10>a)(?P<name11>a)(?P<name12>a)(?P<name13>a)(?P<name14>a)(?P<name15>a)(?P<name16>a)(?P<name17>a)(?P<name18>a)(?P<name19>a)(?P<name20>a)(?P<name21>a)(?P<name22>a)(?P<name23>a)(?P<name24>a)(?P<name25>a)(?P<name26>a)(?P<name27>a)(?P<name28>a)(?P<name29>a)(?P<name30>a)(?P<name31>a)(?P<name32>a)(?P<name33>a)(?P<name34>a)(?P<name35>a)(?P<name36>a)(?P<name37>a)(?P<name38>a)(?P<name39>a)(?P<name40>a)(?P<name41>a)(?P<name42>a)(?P<name43>a)(?P<name44>a)(?P<name45>a)(?P<name46>a)(?P<name47>a)(?P<name48>a)(?P<name49>a)(?P<name50>a)(?P<name51>a)(?P<name52>a)(?P<name53>a)(?P<name54>a)(?P<name55>a)(?P<name56>a)(?P<name57>a)(?P<name58>a)(?P<name59>a)(?P<name60>a)(?P<name61>a)(?P<name62>a)(?P<name63>a)(?P<name64>a)(?P<name65>a)(?P<name66>a)(?P<name67>a)(?P<name68>a)(?P<name69>a)(?P<name70>a)(?P<name71>a)(?P<name72>a)(?P<name73>a)(?P<name74>a)(?P<name75>a)(?P<name76>a)(?P<name77>a)(?P<name78>a)(?P<name79>a)(?P<name80>a)(?P<name81>a)(?P<name82>a)(?P<name83>a)(?P<name84>a)(?P<name85>a)(?P<name86>a)(?P<name87>a)(?P<name88>a)(?P<name89>a)(?P<name90>a)(?P<name91>a)(?P<name92>a)(?P<name93>a)(?P<name94>a)(?P<name95>a)(?P<name96>a)(?P<name97>a)(?P<name98>a)(?P<name99>a)(?P<name100>a)"I
    aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa

"(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)(a)"I
    aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa

/[^()]*(?:\((?R)\)[^()]*)*/I
    (this(and)that
    (this(and)that)
    (this(and)that)stuff

/[^()]*(?:\((?>(?R))\)[^()]*)*/I
    (this(and)that
    (this(and)that)

/[^()]*(?:\((?R)\))*[^()]*/I
    (this(and)that
    (this(and)that)

/(?:\((?R)\))*[^()]*/I
    (this(and)that
    (this(and)that)
    ((this))

/(?:\((?R)\))|[^()]*/I
    (this(and)that
    (this(and)that)
    (this)
    ((this))

/\x{0000ff}/I

/^((?P<A>a1)|(?P<A>a2)b)/I

/^((?P<A>a1)|(?P<A>a2)b)/IJ
    a1b\CA
    a2b\CA
    ** Failers
    a1b\CZ\CA
    
/(?|(?<a>)(?<b>)(?<a>)|(?<a>)(?<b>)(?<a>))/IJ

/^(?P<A>a)(?P<A>b)/IJ
    ab\CA

/^(?P<A>a)(?P<A>b)|cd/IJ
    ab\CA
    cd\CA

/^(?P<A>a)(?P<A>b)|cd(?P<A>ef)(?P<A>gh)/IJ
    cdefgh\CA

/^((?P<A>a1)|(?P<A>a2)b)/IJ
    a1b\GA
    a2b\GA
    ** Failers
    a1b\GZ\GA

/^(?P<A>a)(?P<A>b)/IJ
    ab\GA

/^(?P<A>a)(?P<A>b)|cd/IJ
    ab\GA
    cd\GA

/^(?P<A>a)(?P<A>b)|cd(?P<A>ef)(?P<A>gh)/IJ
    cdefgh\GA

/(?J)^((?P<A>a1)|(?P<A>a2)b)/I
    a1b\CA
    a2b\CA

/^(?P<A>a) (?J:(?P<B>b)(?P<B>c)) (?P<A>d)/I

/ In this next test, J is not set at the outer level; consequently it isn't
set in the pattern's options; consequently pcre_get_named_substring() produces
a random value. /Ix

/^(?P<A>a) (?J:(?P<B>b)(?P<B>c)) (?P<C>d)/I
    a bc d\CA\CB\CC

/^(?P<A>a)?(?(A)a|b)/I
    aabc
    bc
    ** Failers
    abc

/(?:(?(ZZ)a|b)(?P<ZZ>X))+/I
    bXaX

/(?:(?(2y)a|b)(X))+/I

/(?:(?(ZA)a|b)(?P<ZZ>X))+/I

/(?:(?(ZZ)a|b)(?(ZZ)a|b)(?P<ZZ>X))+/I
    bbXaaX

/(?:(?(ZZ)a|\(b\))\\(?P<ZZ>X))+/I
    (b)\\Xa\\X

/(?P<ABC/I

/(?:(?(A)(?P=A)a|b)(?P<A>X|Y))+/I
    bXXaYYaY
    bXYaXXaX

/()()()()()()()()()(?:(?(A)(?P=A)a|b)(?P<A>X|Y))+/I
    bXXaYYaY

/\s*,\s*/IS
    \x0b,\x0b
    \x0c,\x0d

/^abc/Im
    xyz\nabc
    xyz\nabc\<lf>
    xyz\r\nabc\<lf>
    xyz\rabc\<cr>
    xyz\r\nabc\<crlf>
    ** Failers
    xyz\nabc\<cr>
    xyz\r\nabc\<cr>
    xyz\nabc\<crlf>
    xyz\rabc\<crlf>
    xyz\rabc\<lf>

/abc$/Im<lf>
    xyzabc
    xyzabc\n
    xyzabc\npqr
    xyzabc\r\<cr>
    xyzabc\rpqr\<cr>
    xyzabc\r\n\<crlf>
    xyzabc\r\npqr\<crlf>
    ** Failers
    xyzabc\r
    xyzabc\rpqr
    xyzabc\r\n
    xyzabc\r\npqr

/^abc/Im<cr>
    xyz\rabcdef
    xyz\nabcdef\<lf>
    ** Failers
    xyz\nabcdef

/^abc/Im<lf>
    xyz\nabcdef
    xyz\rabcdef\<cr>
    ** Failers
    xyz\rabcdef

/^abc/Im<crlf>
    xyz\r\nabcdef
    xyz\rabcdef\<cr>
    ** Failers
    xyz\rabcdef

/^abc/Im<bad>

/abc/I
    xyz\rabc\<bad>
    abc

/.*/I<lf>
    abc\ndef
    abc\rdef
    abc\r\ndef
    \<cr>abc\ndef
    \<cr>abc\rdef
    \<cr>abc\r\ndef
    \<crlf>abc\ndef
    \<crlf>abc\rdef
    \<crlf>abc\r\ndef

/\w+(.)(.)?def/Is
    abc\ndef
    abc\rdef
    abc\r\ndef

+((?:\s|//.*\\n|/[*](?:\\n|.)*?[*]/)*)+I
   /* this is a C style comment */\M

/(?P<B>25[0-5]|2[0-4]\d|[01]?\d?\d)(?:\.(?P>B)){3}/I

/()()()()()()()()()()()()()()()()()()()()
 ()()()()()()()()()()()()()()()()()()()()
 ()()()()()()()()()()()()()()()()()()()()
 ()()()()()()()()()()()()()()()()()()()()
 ()()()()()()()()()()()()()()()()()()()()
 (.(.))/Ix
    XY\O400

/(a*b|(?i:c*(?-i)d))/IS

/()[ab]xyz/IS

/(|)[ab]xyz/IS

/(|c)[ab]xyz/IS

/(|c?)[ab]xyz/IS

/(d?|c?)[ab]xyz/IS

/(d?|c)[ab]xyz/IS

/^a*b\d/DZ

/^a*+b\d/DZ

/^a*?b\d/DZ

/^a+A\d/DZ
    aaaA5
    ** Failers
    aaaa5

/^a*A\d/IiDZ
    aaaA5
    aaaa5

/(a*|b*)[cd]/IS

/(a+|b*)[cd]/IS

/(a*|b+)[cd]/IS

/(a+|b+)[cd]/IS

/((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((
 ((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((
 (((
 a
 ))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))
 ))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))
 )))
/Ix
  large nest

/a*\d/BZ

/a*\D/BZ

/0*\d/BZ

/0*\D/BZ

/a*\s/BZ

/a*\S/BZ

/ *\s/BZ

/ *\S/BZ

/a*\w/BZ

/a*\W/BZ

/=*\w/BZ

/=*\W/BZ

/\d*a/BZ

/\d*2/BZ

/\d*\d/BZ

/\d*\D/BZ

/\d*\s/BZ

/\d*\S/BZ

/\d*\w/BZ

/\d*\W/BZ

/\D*a/BZ

/\D*2/BZ

/\D*\d/BZ

/\D*\D/BZ

/\D*\s/BZ

/\D*\S/BZ

/\D*\w/BZ

/\D*\W/BZ

/\s*a/BZ

/\s*2/BZ

/\s*\d/BZ

/\s*\D/BZ

/\s*\s/BZ

/\s*\S/BZ

/\s*\w/BZ

/\s*\W/BZ

/\S*a/BZ

/\S*2/BZ

/\S*\d/BZ

/\S*\D/BZ

/\S*\s/BZ

/\S*\S/BZ

/\S*\w/BZ

/\S*\W/BZ

/\w*a/BZ

/\w*2/BZ

/\w*\d/BZ

/\w*\D/BZ

/\w*\s/BZ

/\w*\S/BZ

/\w*\w/BZ

/\w*\W/BZ

/\W*a/BZ

/\W*2/BZ

/\W*\d/BZ

/\W*\D/BZ

/\W*\s/BZ

/\W*\S/BZ

/\W*\w/BZ

/\W*\W/BZ

/[^a]+a/BZ

/[^a]+a/BZi

/[^a]+A/BZi

/[^a]+b/BZ

/[^a]+\d/BZ

/a*[^a]/BZ

/(?P<abc>x)(?P<xyz>y)/I
    xy\Cabc\Cxyz

/(?<abc>x)(?'xyz'y)/I
    xy\Cabc\Cxyz

/(?<abc'x)(?'xyz'y)/I

/(?<abc>x)(?'xyz>y)/I

/(?P'abc'x)(?P<xyz>y)/I

/^(?:(?(ZZ)a|b)(?<ZZ>X))+/
    bXaX
    bXbX
    ** Failers
    aXaX
    aXbX

/^(?P>abc)(?<abcd>xxx)/

/^(?P>abc)(?<abc>x|y)/
    xx
    xy
    yy
    yx

/^(?P>abc)(?P<abc>x|y)/
    xx
    xy
    yy
    yx

/^((?(abc)a|b)(?<abc>x|y))+/
    bxay
    bxby
    ** Failers
    axby

/^(((?P=abc)|X)(?<abc>x|y))+/
    XxXxxx
    XxXyyx
    XxXyxx
    ** Failers
    x

/^(?1)(abc)/
    abcabc

/^(?:(?:\1|X)(a|b))+/
    Xaaa
    Xaba

/^[\E\Qa\E-\Qz\E]+/BZ

/^[a\Q]bc\E]/BZ

/^[a-\Q\E]/BZ

/^(?P>abc)[()](?<abc>)/BZ

/^((?(abc)y)[()](?P<abc>x))+/BZ
    (xy)x

/^(?P>abc)\Q()\E(?<abc>)/BZ

/^(?P>abc)[a\Q(]\E(](?<abc>)/BZ

/^(?P>abc) # this is (a comment)
  (?<abc>)/BZx

/^\W*(?:(?<one>(?<two>.)\W*(?&one)\W*\k<two>|)|(?<three>(?<four>.)\W*(?&three)\W*\k'four'|\W*.\W*))\W*$/Ii
    1221
    Satan, oscillate my metallic sonatas!
    A man, a plan, a canal: Panama!
    Able was I ere I saw Elba.
    *** Failers
    The quick brown fox

/(?=(\w+))\1:/I
    abcd:

/(?=(?'abc'\w+))\k<abc>:/I
    abcd:

/(?'abc'a|b)(?<abc>d|e)\k<abc>{2}/J
    adaa
    ** Failers
    addd
    adbb

/(?'abc'a|b)(?<abc>d|e)(?&abc){2}/J
    bdaa
    bdab
    ** Failers
    bddd

/(?(<bc))/

/(?(''))/

/(?('R')stuff)/

/((abc (?(R) (?(R1)1) (?(R2)2) X  |  (?1)  (?2)   (?R) ))) /x
    abcabc1Xabc2XabcXabcabc

/(?<A> (?'B' abc (?(R) (?(R&A)1) (?(R&B)2) X  |  (?1)  (?2)   (?R) ))) /x
    abcabc1Xabc2XabcXabcabc

/(?<A> (?'B' abc (?(R) (?(R&C)1) (?(R&B)2) X  |  (?1)  (?2)   (?R) ))) /x

/^(?(DEFINE) abc | xyz ) /x

/(?(DEFINE) abc) xyz/xI

/(a|)*\d/
  \O0aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
  \O0aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa4

/^a.b/<lf>
    a\rb
    a\nb\<cr>
    a\x85b\<anycrlf> 
    ** Failers
    a\nb
    a\nb\<any>
    a\rb\<cr>
    a\rb\<any>
    a\x85b\<any> 
    a\rb\<anycrlf>

/^abc./mgx<any>
    abc1 \x0aabc2 \x0babc3xx \x0cabc4 \x0dabc5xx \x0d\x0aabc6 \x85abc7 JUNK

/abc.$/mgx<any>
    abc1\x0a abc2\x0b abc3\x0c abc4\x0d abc5\x0d\x0a abc6\x85 abc7 abc9

/a/<cr><any>

/a/<any><crlf>

/^a\Rb/<bsr_unicode>
    a\nb
    a\rb
    a\r\nb
    a\x0bb
    a\x0cb
    a\x85b
    ** Failers
    a\n\rb

/^a\R*b/<bsr_unicode>
    ab
    a\nb
    a\rb
    a\r\nb
    a\x0bb
    a\x0cb
    a\x85b
    a\n\rb
    a\n\r\x85\x0cb

/^a\R+b/<bsr_unicode>
    a\nb
    a\rb
    a\r\nb
    a\x0bb
    a\x0cb
    a\x85b
    a\n\rb
    a\n\r\x85\x0cb
    ** Failers
    ab

/^a\R{1,3}b/<bsr_unicode>
    a\nb
    a\n\rb
    a\n\r\x85b
    a\r\n\r\nb
    a\r\n\r\n\r\nb
    a\n\r\n\rb
    a\n\n\r\nb
    ** Failers
    a\n\n\n\rb
    a\r

/^a[\R]b/<bsr_unicode>
    aRb
    ** Failers
    a\nb

/(?&abc)X(?<abc>P)/I
    abcPXP123

/(?1)X(?<abc>P)/I
    abcPXP123

/(?:a(?&abc)b)*(?<abc>x)/
    123axbaxbaxbx456
    123axbaxbaxb456

/(?:a(?&abc)b){1,5}(?<abc>x)/
    123axbaxbaxbx456

/(?:a(?&abc)b){2,5}(?<abc>x)/
    123axbaxbaxbx456

/(?:a(?&abc)b){2,}(?<abc>x)/
    123axbaxbaxbx456

/(abc)(?i:(?1))/
   defabcabcxyz
   DEFabcABCXYZ

/(abc)(?:(?i)(?1))/
   defabcabcxyz
   DEFabcABCXYZ

/^(a)\g-2/

/^(a)\g/

/^(a)\g{0}/

/^(a)\g{3/

/^(a)\g{aa}/

/^a.b/<lf>
    a\rb
    *** Failers
    a\nb

/.+foo/
    afoo
    ** Failers
    \r\nfoo
    \nfoo

/.+foo/<crlf>
    afoo
    \nfoo
    ** Failers
    \r\nfoo

/.+foo/<any>
    afoo
    ** Failers
    \nfoo
    \r\nfoo

/.+foo/s
    afoo
    \r\nfoo
    \nfoo
    
/^$/mg<any>
    abc\r\rxyz
    abc\n\rxyz  
    ** Failers 
    abc\r\nxyz

/(?m)^$/<any>g+
    abc\r\n\r\n

/(?m)^$|^\r\n/<any>g+ 
    abc\r\n\r\n
    
/(?m)$/<any>g+ 
    abc\r\n\r\n

/abc.$/mgx<anycrlf>
    abc1\x0a abc2\x0b abc3\x0c abc4\x0d abc5\x0d\x0a abc6\x85 abc9

/^X/m
    XABC
    ** Failers 
    XABC\B

/(ab|c)(?-1)/BZ
    abc

/xy(?+1)(abc)/BZ
    xyabcabc
    ** Failers
    xyabc  
    
/x(?-0)y/

/x(?-1)y/

/x(?+0)y/ 

/x(?+1)y/

/^(abc)?(?(-1)X|Y)/BZ
    abcX
    Y
    ** Failers
    abcY   
    
/^((?(+1)X|Y)(abc))+/BZ 
    YabcXabc
    YabcXabcXabc
    ** Failers
    XabcXabc  

/(?(-1)a)/BZ

/((?(-1)a))/BZ

/((?(-2)a))/BZ

/^(?(+1)X|Y)(.)/BZ
    Y!

/(?<A>tom|bon)-\k{A}/
    tom-tom
    bon-bon 
    ** Failers
    tom-bon  

/\g{A/ 

/(?|(abc)|(xyz))/BZ
   >abc<
   >xyz< 

/(x)(?|(abc)|(xyz))(x)/BZ
    xabcx
    xxyzx 

/(x)(?|(abc)(pqr)|(xyz))(x)/BZ
    xabcpqrx
    xxyzx 

/\H++X/BZ
    ** Failers
    XXXX
    
/\H+\hY/BZ
    XXXX Y 

/\H+ Y/BZ

/\h+A/BZ

/\v*B/BZ

/\V+\x0a/BZ

/A+\h/BZ

/ *\H/BZ

/A*\v/BZ

/\x0b*\V/BZ

/\d+\h/BZ

/\d*\v/BZ

/S+\h\S+\v/BZ

/\w{3,}\h\w+\v/BZ

/\h+\d\h+\w\h+\S\h+\H/BZ

/\v+\d\v+\w\v+\S\v+\V/BZ

/\H+\h\H+\d/BZ

/\V+\v\V+\w/BZ

/\( (?: [^()]* | (?R) )* \)/x
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/a\Rb/I<bsr_unicode>
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/a\R?b/I<bsr_anycrlf>
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/a\R?b/I<bsr_unicode>
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/a(?!)b/BZ

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/X\D{2,4}+b/
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    ** Failers 
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/(^(a|b\g<-1>c))/
    aaaa
    bacxxx
    bbaccxxx 
    bbbacccxx

/(?-i:\g<name>)(?i:(?<name>a))/
    XaaX
    XAAX 

/(?i:\g<name>)(?-i:(?<name>a))/
    XaaX
    ** Failers 
    XAAX 

/(?-i:\g<+1>)(?i:(a))/
    XaaX
    XAAX 

/(?=(?<regex>(?#simplesyntax)\$(?<name>[a-zA-Z_\x{7f}-\x{ff}][a-zA-Z0-9_\x{7f}-\x{ff}]*)(?:\[(?<index>[a-zA-Z0-9_\x{7f}-\x{ff}]+|\$\g<name>)\]|->\g<name>(\(.*?\))?)?|(?#simple syntax withbraces)\$\{(?:\g<name>(?<indices>\[(?:\g<index>|'(?:\\.|[^'\\])*'|"(?:\g<regex>|\\.|[^"\\])*")\])?|\g<complex>|\$\{\g<complex>\})\}|(?#complexsyntax)\{(?<complex>\$(?<segment>\g<name>(\g<indices>*|\(.*?\))?)(?:->\g<segment>)*|\$\g<complex>|\$\{\g<complex>\})\}))\{/

/(?<n>a|b|c)\g<n>*/
   abc
   accccbbb 

/^X(?7)(a)(?|(b)|(q)(r)(s))(c)(d)(Y)/
    XYabcdY

/(?<=b(?1)|zzz)(a)/
    xbaax
    xzzzax 

/(a)(?<=b\1)/

/(a)(?<=b+(?1))/

/(a+)(?<=b(?1))/

/(a(?<=b(?1)))/

/(?<=b(?1))xyz/

/(?<=b(?1))xyz(b+)pqrstuvew/

/(a|bc)\1/SI

/(a|bc)\1{2,3}/SI

/(a|bc)(?1)/SI

/(a|b\1)(a|b\1)/SI

/(a|b\1){2}/SI

/(a|bbbb\1)(a|bbbb\1)/SI

/(a|bbbb\1){2}/SI

/^From +([^ ]+) +[a-zA-Z][a-zA-Z][a-zA-Z] +[a-zA-Z][a-zA-Z][a-zA-Z] +[0-9]?[0-9] +[0-9][0-9]:[0-9][0-9]/SI

/<tr([\w\W\s\d][^<>]{0,})><TD([\w\W\s\d][^<>]{0,})>([\d]{0,}\.)(.*)((<BR>([\w\W\s\d][^<>]{0,})|[\s]{0,}))<\/a><\/TD><TD([\w\W\s\d][^<>]{0,})>([\w\W\s\d][^<>]{0,})<\/TD><TD([\w\W\s\d][^<>]{0,})>([\w\W\s\d][^<>]{0,})<\/TD><\/TR>/isIS

"(?>.*/)foo"SI

/(?(?=[^a-z]+[a-z])  \d{2}-[a-z]{3}-\d{2}  |  \d{2}-\d{2}-\d{2} ) /xSI

/(?:(?:(?:(?:(?:(?:(?:(?:(?:(a|b|c))))))))))/iSI

/(?:c|d)(?:)(?:aaaaaaaa(?:)(?:bbbbbbbb)(?:bbbbbbbb(?:))(?:bbbbbbbb(?:)(?:bbbbbbbb)))/SI

/<a[\s]+href[\s]*=[\s]*          # find <a href=
 ([\"\'])?                       # find single or double quote
 (?(1) (.*?)\1 | ([^\s]+))       # if quote found, match up to next matching
                                 # quote, otherwise match up to next space
/isxSI

/^(?!:)                       # colon disallowed at start
  (?:                         # start of item
    (?: [0-9a-f]{1,4} |       # 1-4 hex digits or
    (?(1)0 | () ) )           # if null previously matched, fail; else null
    :                         # followed by colon
  ){1,7}                      # end item; 1-7 of them required               
  [0-9a-f]{1,4} $             # final hex number at end of string
  (?(1)|.)                    # check that there was an empty component
  /xiIS

/(?|(?<a>A)|(?<a>B))/I
    AB\Ca
    BA\Ca

/(?|(?<a>A)|(?<b>B))/ 

/(?:a(?<quote> (?<apostrophe>')|(?<realquote>")) |
    b(?<quote> (?<apostrophe>')|(?<realquote>")) ) 
    (?('quote')[a-z]+|[0-9]+)/JIx
    a"aaaaa
    b"aaaaa 
    ** Failers 
    b"11111
    a"11111 
    
/^(?|(a)(b)(c)(?<D>d)|(?<D>e)) (?('D')X|Y)/JDZx
    abcdX
    eX
    ** Failers
    abcdY
    ey     
    
/(?<A>a) (b)(c)  (?<A>d  (?(R&A)$ | (?4)) )/JDZx
    abcdd
    ** Failers
    abcdde  

/abcd*/
    xxxxabcd\P
    xxxxabcd\P\P

/abcd*/i
    xxxxabcd\P
    xxxxabcd\P\P
    XXXXABCD\P
    XXXXABCD\P\P

/abc\d*/
    xxxxabc1\P
    xxxxabc1\P\P

/(a)bc\1*/
    xxxxabca\P
    xxxxabca\P\P

/abc[de]*/
    xxxxabcde\P
    xxxxabcde\P\P

/-- This is not in the Perl-compatible test because Perl seems currently to be
    broken and not behaving as specified in that it *does* bumpalong after
    hitting (*COMMIT). --/

/(?1)(A(*COMMIT)|B)D/
    ABD
    XABD
    BAD
    ABXABD  
    ** Failers 
    ABX 
    BAXBAD  

/(\3)(\1)(a)/<JS>
    cat

/(\3)(\1)(a)/SI<JS>
    cat

/(\3)(\1)(a)/SI
    cat

/i(?(DEFINE)(?<s>a))/SI
    i
    
/()i(?(1)a)/SI 
    ia

/(?i)a(?-i)b|c/BZ
    XabX
    XAbX
    CcC 
    ** Failers
    XABX   

/(?i)a(?s)b|c/BZ

/(?i)a(?s-i)b|c/BZ

/^(ab(c\1)d|x){2}$/BZ
    xabcxd
    
/^(?&t)*+(?(DEFINE)(?<t>.))$/BZ

/^(?&t)*(?(DEFINE)(?<t>.))$/BZ

/ -- This one is here because Perl gives the match as "b" rather than "ab". I
     believe this to be a Perl bug. --/  
      
/(?>a\Kb)z|(ab)/
    ab 

/(?P<L1>(?P<L2>0|)|(?P>L2)(?P>L1))/

/abc(*MARK:)pqr/

/abc(*:)pqr/

/abc(*FAIL:123)xyz/

/--- This should, and does, fail. In Perl, it does not, which I think is a 
     bug because replacing the B in the pattern by (B|D) does make it fail. ---/

/A(*COMMIT)B/+K
    ACABX

/--- These should be different, but in Perl they are not, which I think
     is a bug in Perl. ---/

/A(*THEN)B|A(*THEN)C/K
    AC

/A(*PRUNE)B|A(*PRUNE)C/K
    AC
    
/--- Mark names can be duplicated. Perl doesn't give a mark for this one,
though PCRE does. ---/

/^A(*:A)B|^X(*:A)Y/K
    ** Failers
    XAQQ
    
/--- COMMIT at the start of a pattern should be the same as an anchor. Perl 
optimizations defeat this. So does the PCRE optimization unless we disable it 
with \Y. ---/

/(*COMMIT)ABC/
    ABCDEFG
    ** Failers
    DEFGABC\Y  
    
/^(ab (c+(*THEN)cd) | xyz)/x
    abcccd  

/^(ab (c+(*PRUNE)cd) | xyz)/x
    abcccd  

/^(ab (c+(*FAIL)cd) | xyz)/x
    abcccd  
    
/--- Perl gets some of these wrong ---/ 

/(?>.(*ACCEPT))*?5/
    abcde

/(.(*ACCEPT))*?5/
    abcde

/(.(*ACCEPT))5/
    abcde

/(.(*ACCEPT))*5/
    abcde

/A\NB./BZ
    ACBD
    *** Failers
    A\nB
    ACB\n   

/A\NB./sBZ
    ACBD
    ACB\n 
    *** Failers
    A\nB  
  
/A\NB/<crlf>
    A\nB
    A\rB
    ** Failers
    A\r\nB    

/\R+b/BZ

/\R+\n/BZ

/\R+\d/BZ

/\d*\R/BZ

/\s*\R/BZ
    \x20\x0a
    \x20\x0d
    \x20\x0d\x0a

/\S*\R/BZ
    a\x0a

/X\h*\R/BZ
    X\x20\x0a

/X\H*\R/BZ
    X\x0d\x0a

/X\H+\R/BZ
    X\x0d\x0a

/X\H++\R/BZ
    X\x0d\x0a

/(?<=abc)def/
    abc\P\P

/abc$/
    abc
    abc\P
    abc\P\P

/abc$/m
    abc
    abc\n
    abc\P\P
    abc\n\P\P 
    abc\P
    abc\n\P

/abc\z/
    abc
    abc\P
    abc\P\P

/abc\Z/
    abc
    abc\P
    abc\P\P

/abc\b/
    abc
    abc\P
    abc\P\P

/abc\B/
    abc
    abc\P
    abc\P\P

/.+/
    abc\>0
    abc\>1
    abc\>2
    abc\>3
    abc\>4
    abc\>-4 

/^\cģ/

/(?P<abn>(?P=abn)xxx)/BZ

/(a\1z)/BZ

/(?P<abn>(?P=abn)(?<badstufxxx)/BZ

/(?P<abn>(?P=axn)xxx)/BZ

/(?P<abn>(?P=axn)xxx)(?<axn>yy)/BZ

/-- These tests are here because Perl gets the first one wrong. --/

/(\R*)(.)/s
    \r\n
    \r\r\n\n\r 
    \r\r\n\n\r\n 

/(\R)*(.)/s
    \r\n
    \r\r\n\n\r 
    \r\r\n\n\r\n 

/((?>\r\n|\n|\x0b|\f|\r|\x85)*)(.)/s
    \r\n
    \r\r\n\n\r 
    \r\r\n\n\r\n 

/-- --/

/^abc$/BZ

/^abc$/BZm

/^(a)*+(\w)/S
    aaaaX
    ** Failers 
    aaaa

/^(?:a)*+(\w)/S
    aaaaX
    ** Failers 
    aaaa

/(a)++1234/SDZ

/([abc])++1234/SI

/(?<=(abc)+)X/

/(^ab)/I

/(^ab)++/I

/(^ab|^)+/I

/(^ab|^)++/I

/(?:^ab)/I

/(?:^ab)++/I

/(?:^ab|^)+/I

/(?:^ab|^)++/I

/(.*ab)/I

/(.*ab)++/I

/(.*ab|.*)+/I

/(.*ab|.*)++/I

/(?:.*ab)/I

/(?:.*ab)++/I

/(?:.*ab|.*)+/I

/(?:.*ab|.*)++/I

/(?=a)[bcd]/I

/((?=a))[bcd]/I

/((?=a))+[bcd]/I

/((?=a))++[bcd]/I

/(?=a+)[bcd]/iI

/(?=a+?)[bcd]/iI

/(?=a++)[bcd]/iI

/(?=a{3})[bcd]/iI

/(abc)\1+/S

/-- Perl doesn't get these right IMO (the 3rd is PCRE-specific) --/

/(?1)(?:(b(*ACCEPT))){0}/
    b

/(?1)(?:(b(*ACCEPT))){0}c/
    bc
    ** Failers 
    b 

/(?1)(?:((*ACCEPT))){0}c/
    c
    c\N 

/^.*?(?(?=a)a|b(*THEN)c)/
    ba

/^.*?(?(?=a)a|bc)/
    ba

/^.*?(?(?=a)a(*THEN)b|c)/
    ac

/^.*?(?(?=a)a(*THEN)b)c/
    ac

/^.*?(a(*THEN)b)c/
    aabc
    
/^.*? (?1) c (?(DEFINE)(a(*THEN)b))/x
    aabc

/^.*?(a(*THEN)b|z)c/
    aabc

/^.*?(z|a(*THEN)b)c/
    aabc

/-- --/

/-- These studied versions are here because they are not Perl-compatible; the
    studying means the mark is not seen. --/

/(*MARK:A)(*SKIP:B)(C|X)/KS
    C
    D
     
/(*:A)A+(*SKIP:A)(B|Z)/KS
    AAAC

/-- --/

"(?=a*(*ACCEPT)b)c"
    c
    c\N 
    
/(?1)c(?(DEFINE)((*ACCEPT)b))/
    c
    c\N  
    
/(?>(*ACCEPT)b)c/
    c
    c\N  

/(?:(?>(a)))+a%/++
    %aa%

/(a)b|ac/++SS
    ac\O3
    
/(a)(b)x|abc/++
     abc\O6

/(a)bc|(a)(b)\2/
    \O3abc
    \O4abc 

/(?(DEFINE)(a(?2)|b)(b(?1)|a))(?:(?1)|(?2))/SI

/(a(?2)|b)(b(?1)|a)(?:(?1)|(?2))/SI

/(a(?2)|b)(b(?1)|a)(?1)(?2)/SI

/(abc)(?1)/SI

/^(?>a)++/
    aa\M
    aaaaaaaaa\M 
    
/(a)(?1)++/
    aa\M
    aaaaaaaaa\M  

/(?:(foo)|(bar)|(baz))X/SS=
    bazfooX
    foobazbarX
    barfooX
    bazX
    foobarbazX    
    bazfooX\O0
    bazfooX\O2
    bazfooX\O4
    bazfooX\O6
    bazfooX\O8
    bazfooX\O10

/(?=abc){3}abc/BZ

/(?=abc)+abc/BZ

/(?=abc)++abc/BZ

/(?=abc){0}xyz/BZ

/(?=(a))?./BZ

/(?=(a))??./BZ

/^(?=(a)){0}b(?1)/BZ

/(?(DEFINE)(a))?b(?1)/BZ

/^(?=(?1))?[az]([abc])d/BZ

/^(?!a){0}\w+/BZ

/(?<=(abc))?xyz/BZ

/[:a[:abc]b:]/BZ

/((?2))((?1))/SS
    abc

/((?(R2)a+|(?1)b))/SS
    aaaabcde

/(?(R)a*(?1)|((?R))b)/SS
    aaaabcde

/(a+|(?R)b)/

/^(a(*:A)(d|e(*:B))z|aeq)/C
    adz
    aez
    aeqwerty

/.(*F)/
    \P\Pabc

/\btype\b\W*?\btext\b\W*?\bjavascript\b/IS

/\btype\b\W*?\btext\b\W*?\bjavascript\b|\burl\b\W*?\bshell:|<input\b.*?\btype\b\W*?\bimage\b|\bonkeyup\b\W*?\=/IS

/a(*SKIP)c|b(*ACCEPT)|/+S!I
    a

/a(*SKIP)c|b(*ACCEPT)cd(*ACCEPT)|x/SI
    ax

'a*(*ACCEPT)b'+
    \N\N
    abc\N\N
    bbb\N\N 

/(*ACCEPT)a/+I
    bax

/z(*ACCEPT)a/+I
    baxzbx

/a(?:.)*?a/ims                                                                  
    \Mabbbbbbbbbbbbbbbbbbbbba
    
/a(?:.(*THEN))*?a/ims
    \Mabbbbbbbbbbbbbbbbbbbbba

/a(?:.(*THEN:ABC))*?a/ims
    \Mabbbbbbbbbbbbbbbbbbbbba

/^(?>a+)(?>(z+))\w/BZ
    aaaazzzzb
    ** Failers
    aazz  

/(.)(\1|a(?2))/
    bab
    
/\1|(.)(?R)\1/
    cbbbc
    
/(.)((?(1)c|a)|a(?2))/
    baa  

/(?P<abn>(?P=abn)xxx)/BZ

/(a\1z)/BZ

/^(?>a+)(?>b+)(?>c+)(?>d+)(?>e+)/
     \Maabbccddee

/^(?>(a+))(?>(b+))(?>(c+))(?>(d+))(?>(e+))/
     \Maabbccddee

/^(?>(a+))(?>b+)(?>(c+))(?>d+)(?>(e+))/
     \Maabbccddee

/^a\x41z/<JS>
    aAz
    *** Failers
    ax41z

/^a[m\x41]z/<JS>
    aAz

/^a\x1z/<JS>
    ax1z

/^a\u0041z/<JS>
    aAz
    *** Failers
    au0041z

/^a[m\u0041]z/<JS>
    aAz

/^a\u041z/<JS>
    au041z
    *** Failers
    aAz

/^a\U0041z/<JS>
    aU0041z
    *** Failers
    aAz

/(?(?=c)c|d)++Y/BZ

/(?(?=c)c|d)*+Y/BZ

/a[\NB]c/
    aNc
    
/a[B-\Nc]/ 

/a[B\Nc]/ 

/(a)(?2){0,1999}?(b)/

/(a)(?(DEFINE)(b))(?2){0,1999}?(?2)/

/--- This test, with something more complicated than individual letters, causes
different behaviour in Perl. Perhaps it disables some optimization; no tag is
passed back for the failures, whereas in PCRE there is a tag. ---/
    
/(A|P)(*:A)(B|P) | (X|P)(X|P)(*:B)(Y|P)/xK
    AABC
    XXYZ 
    ** Failers
    XAQQ  
    XAQQXZZ  
    AXQQQ 
    AXXQQQ 

/-- Perl doesn't give marks for these, though it does if the alternatives are
replaced by single letters. --/
    
/(b|q)(*:m)f|a(*:n)w/K
    aw 
    ** Failers 
    abc

/(q|b)(*:m)f|a(*:n)w/K
    aw 
    ** Failers 
    abc

/-- After a partial match, the behaviour is as for a failure. --/

/^a(*:X)bcde/K
   abc\P
   
/-- These are here because Perl doesn't return a mark, except for the first --/

/(?=(*:x))(q|)/K+
    abc

/(?=(*:x))((*:y)q|)/K+
    abc

/(?=(*:x))(?:(*:y)q|)/K+
    abc

/(?=(*:x))(?>(*:y)q|)/K+
    abc

/(?=a(*:x))(?!a(*:y)c)/K+
    ab

/(?=a(*:x))(?=a(*:y)c|)/K+
    ab

/(..)\1/
    ab\P
    aba\P
    abab\P

/(..)\1/i
    ab\P
    abA\P
    aBAb\P

/(..)\1{2,}/
    ab\P
    aba\P
    abab\P
    ababa\P
    ababab\P
    ababab\P\P
    abababa\P
    abababa\P\P

/(..)\1{2,}/i
    ab\P
    aBa\P
    aBAb\P
    AbaBA\P
    abABAb\P
    aBAbaB\P\P
    abABabA\P
    abaBABa\P\P

/(..)\1{2,}?x/i
    ab\P
    abA\P
    aBAb\P
    abaBA\P
    abAbaB\P
    abaBabA\P
    abAbABaBx\P

/^(..)\1/
    aba\P

/^(..)\1{2,3}x/
    aba\P
    ababa\P
    ababa\P\P
    abababx
    ababababx  

/^(..)\1{2,3}?x/
    aba\P
    ababa\P
    ababa\P\P
    abababx
    ababababx  
    
/^(..)(\1{2,3})ab/
    abababab

/^\R/
    \r\P
    \r\P\P
    
/^\R{2,3}x/
    \r\P
    \r\P\P
    \r\r\P 
    \r\r\P\P
    \r\r\r\P  
    \r\r\r\P\P
    \r\rx
    \r\r\rx    

/^\R{2,3}?x/
    \r\P
    \r\P\P
    \r\r\P 
    \r\r\P\P
    \r\r\r\P  
    \r\r\r\P\P
    \r\rx
    \r\r\rx    
    
/^\R?x/
    \r\P
    \r\P\P 
    x
    \rx  

/^\R+x/
    \r\P
    \r\P\P 
    \r\n\P
    \r\n\P\P  
    \rx  

/^a$/<CRLF>
    a\r\P
    a\r\P\P 

/^a$/m<CRLF>
    a\r\P
    a\r\P\P 

/^(a$|a\r)/<CRLF>
    a\r\P
    a\r\P\P 

/^(a$|a\r)/m<CRLF>
    a\r\P
    a\r\P\P 

/./<CRLF>
    \r\P
    \r\P\P 
  
/.{2,3}/<CRLF>
    \r\P 
    \r\P\P
    \r\r\P
    \r\r\P\P
    \r\r\r\P
    \r\r\r\P\P     

/.{2,3}?/<CRLF>
    \r\P 
    \r\P\P
    \r\r\P
    \r\r\P\P
    \r\r\r\P
    \r\r\r\P\P     

"AB(C(D))(E(F))?(?(?=\2)(?=\4))"
    ABCDGHI\O03
    
/-- These are all run as real matches in test 1; here we are just checking the
settings of the anchored and startline bits. --/ 

/(?>.*?a)(?<=ba)/I

/(?:.*?a)(?<=ba)/I

/.*?a(*PRUNE)b/I

/.*?a(*PRUNE)b/sI

/^a(*PRUNE)b/sI

/.*?a(*SKIP)b/I

/(?>.*?a)b/sI

/(?>.*?a)b/I

/(?>^a)b/sI

/(?>.*?)(?<=(abcd)|(wxyz))/I

/(?>.*)(?<=(abcd)|(wxyz))/I

"(?>.*)foo"I

"(?>.*?)foo"I

/(?>^abc)/mI

/(?>.*abc)/mI

/(?:.*abc)/mI

/-- Check PCRE_STUDY_EXTRA_NEEDED --/

/.?/S-I

/.?/S!I

/(?:(a)+(?C1)bb|aa(?C2)b)/
    aab\C+
   
/(?:(a)++(?C1)bb|aa(?C2)b)/
    aab\C+ 
    
/(?:(?>(a))(?C1)bb|aa(?C2)b)/
    aab\C+ 

/(?:(?1)(?C1)x|ab(?C2))((a)){0}/                                                
    aab\C+ 

/(?1)(?C1)((a)(?C2)){0}/   
    aab\C+ 

/(?:(a)+(?C1)bb|aa(?C2)b)++/
    aab\C+
    aab\C+\O2

/(ab)x|ab/
    ab\O3
    ab\O2 
  
/(ab)/
    ab\O3
    ab\O2 
    
/(?<=123)(*MARK:xx)abc/K
    xxxx123a\P\P
    xxxx123a\P
    
/123\Kabc/
    xxxx123a\P\P
    xxxx123a\P

/^(?(?=a)aa|bb)/C
    bb

/(?C1)^(?C2)(?(?C99)(?=(?C3)a(?C4))(?C5)a(?C6)a(?C7)|(?C8)b(?C9)b(?C10))(?C11)/
    bb

/-- Perl seems to have a bug with this one --/

/aaaaa(*COMMIT)(*PRUNE)b|a+c/
    aaaaaac
    
/-- Here are some that Perl treats differently because of the way it handles
backtracking verbs. --/

 /(?!a(*COMMIT)b)ac|ad/
     ac
     ad 

/^(?!a(*THEN)b|ac)../
     ac
     ad 

/^(?=a(*THEN)b|ac)/
    ac
    
/\A.*?(?:a|b(*THEN)c)/
    ba

/\A.*?(?:a|b(*THEN)c)++/
    ba

/\A.*?(?:a|b(*THEN)c|d)/
    ba

/(?:(a(*MARK:X)a+(*SKIP:X)b)){0}(?:(?1)|aac)/
    aac 

/\A.*?(a|b(*THEN)c)/
    ba

/^(A(*THEN)B|A(*THEN)D)/
    AD           
    
/(?!b(*THEN)a)bn|bnn/
    bnn

/(?(?=b(*SKIP)a)bn|bnn)/
    bnn

/(?=b(*THEN)a|)bn|bnn/
    bnn

/-------------------------/ 

/(*LIMIT_MATCH=12bc)abc/

/(*LIMIT_MATCH=4294967290)abc/

/(*LIMIT_RECURSION=4294967280)abc/I

/(a+)*zz/
    aaaaaaaaaaaaaz
    aaaaaaaaaaaaaz\q3000

/(a+)*zz/S-
    aaaaaaaaaaaaaz\Q10 

/(*LIMIT_MATCH=3000)(a+)*zz/I
    aaaaaaaaaaaaaz
    aaaaaaaaaaaaaz\q60000

/(*LIMIT_MATCH=60000)(*LIMIT_MATCH=3000)(a+)*zz/I
    aaaaaaaaaaaaaz

/(*LIMIT_MATCH=60000)(a+)*zz/I
    aaaaaaaaaaaaaz
    aaaaaaaaaaaaaz\q3000

/(*LIMIT_RECURSION=10)(a+)*zz/IS-
    aaaaaaaaaaaaaz
    aaaaaaaaaaaaaz\Q1000

/(*LIMIT_RECURSION=10)(*LIMIT_RECURSION=1000)(a+)*zz/IS-
    aaaaaaaaaaaaaz

/(*LIMIT_RECURSION=1000)(a+)*zz/IS-
    aaaaaaaaaaaaaz
    aaaaaaaaaaaaaz\Q10

/-- This test causes a segfault with Perl 5.18.0 --/

/^(?=(a)){0}b(?1)/
    backgammon

/(?|(?<n>f)|(?<n>b))/JI

/(?<a>abc)(?<a>z)\k<a>()/JDZS

/a*[bcd]/BZ

/[bcd]*a/BZ

/-- A complete set of tests for auto-possessification of character types --/

/\D+\D \D+\d \D+\S \D+\s \D+\W \D+\w \D+. \D+\C \D+\R \D+\H \D+\h \D+\V \D+\v \D+\Z \D+\z \D+$/BZx

/\d+\D \d+\d \d+\S \d+\s \d+\W \d+\w \d+. \d+\C \d+\R \d+\H \d+\h \d+\V \d+\v \d+\Z \d+\z \d+$/BZx

/\S+\D \S+\d \S+\S \S+\s \S+\W \S+\w \S+. \S+\C \S+\R \S+\H \S+\h \S+\V \S+\v \S+\Z \S+\z \S+$/BZx

/\s+\D \s+\d \s+\S \s+\s \s+\W \s+\w \s+. \s+\C \s+\R \s+\H \s+\h \s+\V \s+\v \s+\Z \s+\z \s+$/BZx

/\W+\D \W+\d \W+\S \W+\s \W+\W \W+\w \W+. \W+\C \W+\R \W+\H \W+\h \W+\V \W+\v \W+\Z \W+\z \W+$/BZx

/\w+\D \w+\d \w+\S \w+\s \w+\W \w+\w \w+. \w+\C \w+\R \w+\H \w+\h \w+\V \w+\v \w+\Z \w+\z \w+$/BZx

/\C+\D \C+\d \C+\S \C+\s \C+\W \C+\w \C+. \C+\C \C+\R \C+\H \C+\h \C+\V \C+\v \C+\Z \C+\z \C+$/BZx

/\R+\D \R+\d \R+\S \R+\s \R+\W \R+\w \R+. \R+\C \R+\R \R+\H \R+\h \R+\V \R+\v \R+\Z \R+\z \R+$/BZx

/\H+\D \H+\d \H+\S \H+\s \H+\W \H+\w \H+. \H+\C \H+\R \H+\H \H+\h \H+\V \H+\v \H+\Z \H+\z \H+$/BZx

/\h+\D \h+\d \h+\S \h+\s \h+\W \h+\w \h+. \h+\C \h+\R \h+\H \h+\h \h+\V \h+\v \h+\Z \h+\z \h+$/BZx

/\V+\D \V+\d \V+\S \V+\s \V+\W \V+\w \V+. \V+\C \V+\R \V+\H \V+\h \V+\V \V+\v \V+\Z \V+\z \V+$/BZx

/\v+\D \v+\d \v+\S \v+\s \v+\W \v+\w \v+. \v+\C \v+\R \v+\H \v+\h \v+\V \v+\v \v+\Z \v+\z \v+$/BZx

/ a+\D  a+\d  a+\S  a+\s  a+\W  a+\w  a+.  a+\C  a+\R  a+\H  a+\h  a+\V  a+\v  a+\Z  a+\z  a+$/BZx

/\n+\D \n+\d \n+\S \n+\s \n+\W \n+\w \n+. \n+\C \n+\R \n+\H \n+\h \n+\V \n+\v \n+\Z \n+\z \n+$/BZx

/ .+\D  .+\d  .+\S  .+\s  .+\W  .+\w  .+.  .+\C  .+\R  .+\H  .+\h  .+\V  .+\v  .+\Z  .+\z  .+$/BZx

/ .+\D  .+\d  .+\S  .+\s  .+\W  .+\w  .+.  .+\C  .+\R  .+\H  .+\h  .+\V  .+\v  .+\Z  .+\z  .+$/BZxs

/\D+$  \d+$  \S+$  \s+$  \W+$  \w+$  \C+$  \R+$  \H+$  \h+$  \V+$  \v+$   a+$  \n+$   .+$  .+$/BZxm

/(?=a+)a(a+)++a/BZ

/a+(bb|cc)a+(?:bb|cc)a+(?>bb|cc)a+(?:bb|cc)+a+(aa)a+(?:bb|aa)/BZ

/a+(bb|cc)?#a+(?:bb|cc)??#a+(?:bb|cc)?+#a+(?:bb|cc)*#a+(bb|cc)?a#a+(?:aa)?/BZ

/a+(?:bb)?a#a+(?:|||)#a+(?:|b)a#a+(?:|||)?a/BZ

/[ab]*/BZ
    aaaa

/[ab]*?/BZ
    aaaa

/[ab]?/BZ
    aaaa

/[ab]??/BZ
    aaaa

/[ab]+/BZ
    aaaa

/[ab]+?/BZ
    aaaa

/[ab]{2,3}/BZ
    aaaa

/[ab]{2,3}?/BZ
    aaaa

/[ab]{2,}/BZ
    aaaa

/[ab]{2,}?/BZ
    aaaa

/\d+\s{0,5}=\s*\S?=\w{0,4}\W*/BZ

/[a-d]{5,12}[e-z0-9]*#[^a-z]+[b-y]*a[2-7]?[^0-9a-z]+/BZ

/[a-z]*\s#[ \t]?\S#[a-c]*\S#[C-G]+?\d#[4-8]*\D#[4-9,]*\D#[!$]{0,5}\w#[M-Xf-l]+\W#[a-c,]?\W/BZ

/a+(aa|bb)*c#a*(bb|cc)*a#a?(bb|cc)*d#[a-f]*(g|hh)*f/BZ

/[a-f]*(g|hh|i)*i#[a-x]{4,}(y{0,6})*y#[a-k]+(ll|mm)+n/BZ

/[a-f]*(?>gg|hh)+#[a-f]*(?>gg|hh)?#[a-f]*(?>gg|hh)*a#[a-f]*(?>gg|hh)*h/BZ

/[a-c]*d/DZS

/[a-c]+d/DZS

/[a-c]?d/DZS

/[a-c]{4,6}d/DZS

/[a-c]{0,6}d/DZS

/-- End of special auto-possessive tests --/

/^A\o{1239}B/
    A\123B

/^A\oB/
    
/^A\x{zz}B/ 

/^A\x{12Z/

/^A\x{/

/[ab]++/BZO

/[^ab]*+/BZO

/a{4}+/BZO

/a{4}+/BZOi

/[a-[:digit:]]+/

/[A-[:digit:]]+/

/[a-[.xxx.]]+/

/[a-[=xxx=]]+/

/[a-[!xxx!]]+/

/[A-[!xxx!]]+/
    A]]]

/[a-\d]+/

/(?<0abc>xx)/

/(?&1abc)xx(?<1abc>y)/

/(?<ab-cd>xx)/

/(?'0abc'xx)/

/(?P<0abc>xx)/

/\k<5ghj>/

/\k'5ghj'/

/\k{2fgh}/

/(?P=8yuki)/

/\g{4df}/

/(?&1abc)xx(?<1abc>y)/

/(?P>1abc)xx(?<1abc>y)/

/\g'3gh'/

/\g<5fg>/

/(?(<4gh>)abc)/

/(?('4gh')abc)/

/(?(4gh)abc)/

/(?(R&6yh)abc)/

/(((a\2)|(a*)\g<-1>))*a?/BZ

/-- Test the ugly "start or end of word" compatibility syntax --/

/[[:<:]]red[[:>:]]/BZ
    little red riding hood
    a /red/ thing 
    red is a colour
    put it all on red  
    ** Failers
    no reduction
    Alfred Winifred
    
/[a[:<:]] should give error/ 

/(?=ab\K)/+
    abcd

/abcd/f<lf>
    xx\nxabcd
    
/ -- Test stack check external calls --/ 

/(((((a)))))/Q0

/(((((a)))))/Q1

/(((((a)))))/Q

/^\w+(?>\s*)(?<=\w)/BZ

/\othing/

/\o{}/

/\o{whatever}/

/\xthing/

/\x{}/

/\x{whatever}/

"((?=(?(?=(?(?=(?(?=()))))))))"
    a

"(?(?=)==)(((((((((?=)))))))))"
    a

/^(?:(a)|b)(?(1)A|B)/I
    aA123\O3
    aA123\O6

'^(?:(?<AA>a)|b)(?(<AA>)A|B)'
    aA123\O3
    aA123\O6

'^(?<AA>)(?:(?<AA>a)|b)(?(<AA>)A|B)'J
    aA123\O3
    aA123\O6

'^(?:(?<AA>X)|)(?:(?<AA>a)|b)\k{AA}'J
    aa123\O3
    aa123\O6

/(?<N111>(?J)(?<N111>1(111111)11|)1|1|)(?(<N111>)1)/

/(?(?=0)?)+/

/(?(?=0)(?=00)?00765)/
     00765

/(?(?=0)(?=00)?00765|(?!3).56)/
     00765
     456
     ** Failers
     356   

'^(a)*+(\w)'
    g
    g\O3

'^(?:a)*+(\w)'
    g
    g\O3

//C
    \O\C+

"((?2){0,1999}())?"

/((?+1)(\1))/BZ

/(?(?!)a|b)/
    bbb
    aaa 

"((?2)+)((?1))"

"(?(?<E>.*!.*)?)"

"X((?2)()*+){2}+"BZ

"X((?2)()*+){2}"BZ

"(?<=((?2))((?1)))"

/(?<=\Ka)/g+
    aaaaa

/(?<=\Ka)/G+
    aaaaa

/((?2){73}(?2))((?1))/

/.((?2)(?R)\1)()/BZ

/(?1)()((((((\1++))\x85)+)|))/

/(\9*+(?2);\3++()2|)++{/

/\V\x85\9*+((?2)\3++()2)*:2/

/(((?(R)){0,2}) (?''((?'R')((?'R')))))/J

/(((?(X)){0,2}) (?''((?'X')((?'X')))))/J

/(((?(R)){0,2}) (?''((?'X')((?'R')))))/

"(?J)(?'d'(?'d'\g{d}))"

".*?\h.+.\.+\R*?\xd(?i)(?=!(?=b`b`b`\`b\xa9b!)`\a`bbbbbbbbbbbbb`bbbbbbbbbbbb*R\x85bbbbbbb\C?{((?2)(?))((
\H){8(?<=(?1){29}\xa8bbbb\x16\xd\xc6^($(?<! )(\xa9H4){4}h}1)B))\x15')"

"(?J:(?|(?'R')(\k'R')|((?'R'))))"

/(?<=|(\,\$(?73591620449005828816)\xa8.{7}){6}\x09)/

//
\O1

/^(?:(?(1)x|)+)+$()/BZ

/(?=di(?<=(?1))|(?=(.))))/

/(?(R))*+/BZ

/[[:\\](?'abc')[a:]/

"[[[.\xe8Nq\xffq\xff\xe0\x2|||::Nq\xffq\xff\xe0\x6\x2|||::[[[:[::::::[[[[[::::::::[:[[[:[:::[[[[[[[[[[[[:::::::::::::::::[[.\xe8Nq\xffq\xff\xe0\x2|||::Nq\xffq\xff\xe0\x6\x2|||::[[[:[::::::[[[[[::::::::[:[[[:[:::[[[[[[[[[[[[[[:::E[[[:[:[[:[:::[[:::E[[[:[:[[:'[:::::E[[[:[::::::[[[:[[[[[[[::E[[[:[::::::[[[:[[[[[[[[:[[::[::::[[:::::::[[:[[[[[[[:[[::[:[[:[~"

/()(?(R)0)*+/BZ

/(?R-:(?</

/(?1){3918}(((((0(\k'R'))))(?J)(?'R'(?'R'\3){99})))/I

/(?J:(?|(:(?|(?'R')(\k'R')|((?'R')))H'Rk'Rf)|s(?'R')))/

/0(?0)|(1)(*THEN)(*SKIP:0)(*FAIL)/
    01

/((?(R8000000000)))/ 

/(?(8000000000/

/(?:ab)?(?:ab)(?:ab)/
    abab
    ababab
    aba

/((*MARK:A))++a(*SKIP:B)b/
    aacb

/(?J:(?|(:(?|(?'R')(\z(?|(?'R')(\k'R')|((?'R')))k'R')|((?'R')))H'Ak'Rf)|s(?'R')))/

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/L(?#(|++<!(2)?/BZ

/L(?#(|++<!(2)?/BOZ

/L(?#(|++<!(2)?/BCZ

/L(?#(|++<!(2)?/BCOZ

/(A*)\E+/CBZ

/()\Q\E*]/BCZ

/(?<A>)(?J:(?<B>)(?<B>))(?<C>)/
    \O\CC

/(?=a\K)/ 
    ring bpattingbobnd $ 1,oern cou \rb\L

/(?<=((?C)0))/
    9010
    abcd
     
/((?J)(?'R'(?'R'(?'R'(?'R'(?'R'(?|(\k'R'))))))))/

/\N(?(?C)0?!.)*/

/(?<RA>abc)(?(R)xyz)/BZ

/(?<R>abc)(?(R)xyz)/BZ

/(?=.*[A-Z])/I

"(?<=(a))\1?b"
    ab
    aaab 

"(?=(a))\1?b"
    ab
    aaab 

/(?(?=^))b/
    abc

/-- End of testinput2 --/