/the quick brown fox/ the quick brown fox 0: the quick brown fox The quick brown FOX No match What do you know about the quick brown fox? 0: the quick brown fox What do you know about THE QUICK BROWN FOX? No match /The quick brown fox/i the quick brown fox 0: the quick brown fox The quick brown FOX 0: The quick brown FOX What do you know about the quick brown fox? 0: the quick brown fox What do you know about THE QUICK BROWN FOX? 0: THE QUICK BROWN FOX /abcd\t\n\r\f\a\e\071\x3b\$\\\?caxyz/ abcd\t\n\r\f\a\e9;\$\\?caxyz 0: abcd\x09\x0a\x0d\x0c\x07\x1b9;$\?caxyz /a*abc?xyz+pqr{3}ab{2,}xy{4,5}pq{0,6}AB{0,}zz/ abxyzpqrrrabbxyyyypqAzz 0: abxyzpqrrrabbxyyyypqAzz abxyzpqrrrabbxyyyypqAzz 0: abxyzpqrrrabbxyyyypqAzz aabxyzpqrrrabbxyyyypqAzz 0: aabxyzpqrrrabbxyyyypqAzz aaabxyzpqrrrabbxyyyypqAzz 0: aaabxyzpqrrrabbxyyyypqAzz aaaabxyzpqrrrabbxyyyypqAzz 0: aaaabxyzpqrrrabbxyyyypqAzz abcxyzpqrrrabbxyyyypqAzz 0: abcxyzpqrrrabbxyyyypqAzz aabcxyzpqrrrabbxyyyypqAzz 0: aabcxyzpqrrrabbxyyyypqAzz aaabcxyzpqrrrabbxyyyypAzz 0: aaabcxyzpqrrrabbxyyyypAzz aaabcxyzpqrrrabbxyyyypqAzz 0: aaabcxyzpqrrrabbxyyyypqAzz aaabcxyzpqrrrabbxyyyypqqAzz 0: aaabcxyzpqrrrabbxyyyypqqAzz aaabcxyzpqrrrabbxyyyypqqqAzz 0: aaabcxyzpqrrrabbxyyyypqqqAzz aaabcxyzpqrrrabbxyyyypqqqqAzz 0: aaabcxyzpqrrrabbxyyyypqqqqAzz aaabcxyzpqrrrabbxyyyypqqqqqAzz 0: aaabcxyzpqrrrabbxyyyypqqqqqAzz aaabcxyzpqrrrabbxyyyypqqqqqqAzz 0: aaabcxyzpqrrrabbxyyyypqqqqqqAzz aaaabcxyzpqrrrabbxyyyypqAzz 0: aaaabcxyzpqrrrabbxyyyypqAzz abxyzzpqrrrabbxyyyypqAzz 0: abxyzzpqrrrabbxyyyypqAzz aabxyzzzpqrrrabbxyyyypqAzz 0: aabxyzzzpqrrrabbxyyyypqAzz aaabxyzzzzpqrrrabbxyyyypqAzz 0: aaabxyzzzzpqrrrabbxyyyypqAzz aaaabxyzzzzpqrrrabbxyyyypqAzz 0: aaaabxyzzzzpqrrrabbxyyyypqAzz abcxyzzpqrrrabbxyyyypqAzz 0: abcxyzzpqrrrabbxyyyypqAzz aabcxyzzzpqrrrabbxyyyypqAzz 0: aabcxyzzzpqrrrabbxyyyypqAzz aaabcxyzzzzpqrrrabbxyyyypqAzz 0: aaabcxyzzzzpqrrrabbxyyyypqAzz aaaabcxyzzzzpqrrrabbxyyyypqAzz 0: aaaabcxyzzzzpqrrrabbxyyyypqAzz aaaabcxyzzzzpqrrrabbbxyyyypqAzz 0: aaaabcxyzzzzpqrrrabbbxyyyypqAzz aaaabcxyzzzzpqrrrabbbxyyyyypqAzz 0: aaaabcxyzzzzpqrrrabbbxyyyyypqAzz aaabcxyzpqrrrabbxyyyypABzz 0: aaabcxyzpqrrrabbxyyyypABzz aaabcxyzpqrrrabbxyyyypABBzz 0: aaabcxyzpqrrrabbxyyyypABBzz >>>aaabxyzpqrrrabbxyyyypqAzz 0: aaabxyzpqrrrabbxyyyypqAzz >aaaabxyzpqrrrabbxyyyypqAzz 0: aaaabxyzpqrrrabbxyyyypqAzz >>>>abcxyzpqrrrabbxyyyypqAzz 0: abcxyzpqrrrabbxyyyypqAzz *** Failers No match abxyzpqrrabbxyyyypqAzz No match abxyzpqrrrrabbxyyyypqAzz No match abxyzpqrrrabxyyyypqAzz No match aaaabcxyzzzzpqrrrabbbxyyyyyypqAzz No match aaaabcxyzzzzpqrrrabbbxyyypqAzz No match aaabcxyzpqrrrabbxyyyypqqqqqqqAzz No match /^(abc){1,2}zz/ abczz 0: abczz 1: abc abcabczz 0: abcabczz 1: abc *** Failers No match zz No match abcabcabczz No match >>abczz No match /^(b+?|a){1,2}?c/ bc 0: bc 1: b bbc 0: bbc 1: b bbbc 0: bbbc 1: bb bac 0: bac 1: a bbac 0: bbac 1: a aac 0: aac 1: a abbbbbbbbbbbc 0: abbbbbbbbbbbc 1: bbbbbbbbbbb bbbbbbbbbbbac 0: bbbbbbbbbbbac 1: a *** Failers No match aaac No match abbbbbbbbbbbac No match /^(b+|a){1,2}c/ bc 0: bc 1: b bbc 0: bbc 1: bb bbbc 0: bbbc 1: bbb bac 0: bac 1: a bbac 0: bbac 1: a aac 0: aac 1: a abbbbbbbbbbbc 0: abbbbbbbbbbbc 1: bbbbbbbbbbb bbbbbbbbbbbac 0: bbbbbbbbbbbac 1: a *** Failers No match aaac No match abbbbbbbbbbbac No match /^(b+|a){1,2}?bc/ bbc 0: bbc 1: b /^(b*|ba){1,2}?bc/ babc 0: babc 1: ba bbabc 0: bbabc 1: ba bababc 0: bababc 1: ba *** Failers No match bababbc No match babababc No match /^(ba|b*){1,2}?bc/ babc 0: babc 1: ba bbabc 0: bbabc 1: ba bababc 0: bababc 1: ba *** Failers No match bababbc No match babababc No match /^\ca\cA\c[\c{\c:/ \x01\x01\e;z 0: \x01\x01\x1b;z /^[ab\]cde]/ athing 0: a bthing 0: b ]thing 0: ] cthing 0: c dthing 0: d ething 0: e *** Failers No match fthing No match [thing No match \\thing No match /^[]cde]/ ]thing 0: ] cthing 0: c dthing 0: d ething 0: e *** Failers No match athing No match fthing No match /^[^ab\]cde]/ fthing 0: f [thing 0: [ \\thing 0: \ *** Failers 0: * athing No match bthing No match ]thing No match cthing No match dthing No match ething No match /^[^]cde]/ athing 0: a fthing 0: f *** Failers 0: * ]thing No match cthing No match dthing No match ething No match /^\/ 0: \x81 /^/ 0: \xff /^[0-9]+$/ 0 0: 0 1 0: 1 2 0: 2 3 0: 3 4 0: 4 5 0: 5 6 0: 6 7 0: 7 8 0: 8 9 0: 9 10 0: 10 100 0: 100 *** Failers No match abc No match /^.*nter/ enter 0: enter inter 0: inter uponter 0: uponter /^xxx[0-9]+$/ xxx0 0: xxx0 xxx1234 0: xxx1234 *** Failers No match xxx No match /^.+[0-9][0-9][0-9]$/ x123 0: x123 xx123 0: xx123 123456 0: 123456 *** Failers No match 123 No match x1234 0: x1234 /^.+?[0-9][0-9][0-9]$/ x123 0: x123 xx123 0: xx123 123456 0: 123456 *** Failers No match 123 No match x1234 0: x1234 /^([^!]+)!(.+)=apquxz\.ixr\.zzz\.ac\.uk$/ abc!pqr=apquxz.ixr.zzz.ac.uk 0: abc!pqr=apquxz.ixr.zzz.ac.uk 1: abc 2: pqr *** Failers No match !pqr=apquxz.ixr.zzz.ac.uk No match abc!=apquxz.ixr.zzz.ac.uk No match abc!pqr=apquxz:ixr.zzz.ac.uk No match abc!pqr=apquxz.ixr.zzz.ac.ukk No match /:/ Well, we need a colon: somewhere 0: : *** Fail if we don't No match /([\da-f:]+)$/i 0abc 0: 0abc 1: 0abc abc 0: abc 1: abc fed 0: fed 1: fed E 0: E 1: E :: 0: :: 1: :: 5f03:12C0::932e 0: 5f03:12C0::932e 1: 5f03:12C0::932e fed def 0: def 1: def Any old stuff 0: ff 1: ff *** Failers No match 0zzz No match gzzz No match fed\x20 No match Any old rubbish No match /^.*\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})$/ .1.2.3 0: .1.2.3 1: 1 2: 2 3: 3 A.12.123.0 0: A.12.123.0 1: 12 2: 123 3: 0 *** Failers No match .1.2.3333 No match 1.2.3 No match 1234.2.3 No match /^(\d+)\s+IN\s+SOA\s+(\S+)\s+(\S+)\s*\(\s*$/ 1 IN SOA non-sp1 non-sp2( 0: 1 IN SOA non-sp1 non-sp2( 1: 1 2: non-sp1 3: non-sp2 1 IN SOA non-sp1 non-sp2 ( 0: 1 IN SOA non-sp1 non-sp2 ( 1: 1 2: non-sp1 3: non-sp2 *** Failers No match 1IN SOA non-sp1 non-sp2( No match /^[a-zA-Z\d][a-zA-Z\d\-]*(\.[a-zA-Z\d][a-zA-z\d\-]*)*\.$/ a. 0: a. Z. 0: Z. 2. 0: 2. ab-c.pq-r. 0: ab-c.pq-r. 1: .pq-r sxk.zzz.ac.uk. 0: sxk.zzz.ac.uk. 1: .uk x-.y-. 0: x-.y-. 1: .y- *** Failers No match -abc.peq. No match /^\*\.[a-z]([a-z\-\d]*[a-z\d]+)?(\.[a-z]([a-z\-\d]*[a-z\d]+)?)*$/ *.a 0: *.a *.b0-a 0: *.b0-a 1: 0-a *.c3-b.c 0: *.c3-b.c 1: 3-b 2: .c *.c-a.b-c 0: *.c-a.b-c 1: -a 2: .b-c 3: -c *** Failers No match *.0 No match *.a- No match *.a-b.c- No match *.c-a.0-c No match /^(?=ab(de))(abd)(e)/ abde 0: abde 1: de 2: abd 3: e /^(?!(ab)de|x)(abd)(f)/ abdf 0: abdf 1: 2: abd 3: f /^(?=(ab(cd)))(ab)/ abcd 0: ab 1: abcd 2: cd 3: ab /^[\da-f](\.[\da-f])*$/i a.b.c.d 0: a.b.c.d 1: .d A.B.C.D 0: A.B.C.D 1: .D a.b.c.1.2.3.C 0: a.b.c.1.2.3.C 1: .C /^\".*\"\s*(;.*)?$/ \"1234\" 0: "1234" \"abcd\" ; 0: "abcd" ; 1: ; \"\" ; rhubarb 0: "" ; rhubarb 1: ; rhubarb *** Failers No match \"1234\" : things No match /^$/ \ 0: *** Failers No match / ^ a (?# begins with a) b\sc (?# then b c) $ (?# then end)/x ab c 0: ab c *** Failers No match abc No match ab cde No match /(?x) ^ a (?# begins with a) b\sc (?# then b c) $ (?# then end)/ ab c 0: ab c *** Failers No match abc No match ab cde No match /^ a\ b[c ]d $/x a bcd 0: a bcd a b d 0: a b d *** Failers No match abcd No match ab d No match /^(a(b(c)))(d(e(f)))(h(i(j)))(k(l(m)))$/ abcdefhijklm 0: abcdefhijklm 1: abc 2: bc 3: c 4: def 5: ef 6: f 7: hij 8: ij 9: j 10: klm 11: lm 12: m /^(?:a(b(c)))(?:d(e(f)))(?:h(i(j)))(?:k(l(m)))$/ abcdefhijklm 0: abcdefhijklm 1: bc 2: c 3: ef 4: f 5: ij 6: j 7: lm 8: m /^[\w][\W][\s][\S][\d][\D][\b][\n][\c]][\022]/ a+ Z0+\x08\n\x1d\x12 0: a+ Z0+\x08\x0a\x1d\x12 /^[.^$|()*+?{,}]+/ .^\$(*+)|{?,?} 0: .^$(*+)|{?,?} /^a*\w/ z 0: z az 0: az aaaz 0: aaaz a 0: a aa 0: aa aaaa 0: aaaa a+ 0: a aa+ 0: aa /^a*?\w/ z 0: z az 0: a aaaz 0: a a 0: a aa 0: a aaaa 0: a a+ 0: a aa+ 0: a /^a+\w/ az 0: az aaaz 0: aaaz aa 0: aa aaaa 0: aaaa aa+ 0: aa /^a+?\w/ az 0: az aaaz 0: aa aa 0: aa aaaa 0: aa aa+ 0: aa /^\d{8}\w{2,}/ 1234567890 0: 1234567890 12345678ab 0: 12345678ab 12345678__ 0: 12345678__ *** Failers No match 1234567 No match /^[aeiou\d]{4,5}$/ uoie 0: uoie 1234 0: 1234 12345 0: 12345 aaaaa 0: aaaaa *** Failers No match 123456 No match /^[aeiou\d]{4,5}?/ uoie 0: uoie 1234 0: 1234 12345 0: 1234 aaaaa 0: aaaa 123456 0: 1234 /\A(abc|def)=(\1){2,3}\Z/ abc=abcabc 0: abc=abcabc 1: abc 2: abc def=defdefdef 0: def=defdefdef 1: def 2: def *** Failers No match abc=defdef No match /^(a)(b)(c)(d)(e)(f)(g)(h)(i)(j)(k)\11*(\3\4)\1(?#)2$/ abcdefghijkcda2 0: abcdefghijkcda2 1: a 2: b 3: c 4: d 5: e 6: f 7: g 8: h 9: i 10: j 11: k 12: cd abcdefghijkkkkcda2 0: abcdefghijkkkkcda2 1: a 2: b 3: c 4: d 5: e 6: f 7: g 8: h 9: i 10: j 11: k 12: cd /(cat(a(ract|tonic)|erpillar)) \1()2(3)/ cataract cataract23 0: cataract cataract23 1: cataract 2: aract 3: ract 4: 5: 3 catatonic catatonic23 0: catatonic catatonic23 1: catatonic 2: atonic 3: tonic 4: 5: 3 caterpillar caterpillar23 0: caterpillar caterpillar23 1: caterpillar 2: erpillar 3: 4: 5: 3 /^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]/ From abcd Mon Sep 01 12:33:02 1997 0: From abcd Mon Sep 01 12:33 1: abcd /^From\s+\S+\s+([a-zA-Z]{3}\s+){2}\d{1,2}\s+\d\d:\d\d/ From abcd Mon Sep 01 12:33:02 1997 0: From abcd Mon Sep 01 12:33 1: Sep From abcd Mon Sep 1 12:33:02 1997 0: From abcd Mon Sep 1 12:33 1: Sep *** Failers No match From abcd Sep 01 12:33:02 1997 No match /^12.34/s 12\n34 0: 12\x0a34 12\r34 0: 12\x0d34 /\w+(?=\t)/ the quick brown\t fox 0: brown /foo(?!bar)(.*)/ foobar is foolish see? 0: foolish see? 1: lish see? /(?:(?!foo)...|^.{0,2})bar(.*)/ foobar crowbar etc 0: rowbar etc 1: etc barrel 0: barrel 1: rel 2barrel 0: 2barrel 1: rel A barrel 0: A barrel 1: rel /^(\D*)(?=\d)(?!123)/ abc456 0: abc 1: abc *** Failers No match abc123 No match /^1234(?# test newlines inside)/ 1234 0: 1234 /^1234 #comment in extended re /x 1234 0: 1234 /#rhubarb abcd/x abcd 0: abcd /^abcd#rhubarb/x abcd 0: abcd /^(a)\1{2,3}(.)/ aaab 0: aaab 1: a 2: b aaaab 0: aaaab 1: a 2: b aaaaab 0: aaaaa 1: a 2: a aaaaaab 0: aaaaa 1: a 2: a /(?!^)abc/ the abc 0: abc *** Failers No match abc No match /(?=^)abc/ abc 0: abc *** Failers No match the abc No match /^[ab]{1,3}(ab*|b)/ aabbbbb 0: aabb 1: b /^[ab]{1,3}?(ab*|b)/ aabbbbb 0: aabbbbb 1: abbbbb /^[ab]{1,3}?(ab*?|b)/ aabbbbb 0: aa 1: a /^[ab]{1,3}(ab*?|b)/ aabbbbb 0: aabb 1: b / (?: [\040\t] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] )* \) )* \) )* # optional leading comment (?: (?: [^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+ # some number of atom characters... (?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom | " (?: # opening quote... [^\\\x80-\xff\n\015"] # Anything except backslash and quote | # or \\ [^\x80-\xff] # Escaped something (something != CR) )* " # closing quote ) # initial word (?: (?: [\040\t] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] )* \) )* \) )* \. (?: [\040\t] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] )* \) )* \) )* (?: [^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+ # some number of atom characters... (?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom | " (?: # opening quote... [^\\\x80-\xff\n\015"] # Anything except backslash and quote | # or \\ [^\x80-\xff] # Escaped something (something != CR) )* " # closing quote ) )* # further okay, if led by a period (?: [\040\t] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] )* \) )* \) )* @ (?: [\040\t] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] )* \) )* \) )* (?: [^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+ # some number of atom characters... (?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom | \[ # [ (?: [^\\\x80-\xff\n\015\[\]] | \\ [^\x80-\xff] )* # stuff \] # ] ) # initial subdomain (?: # (?: [\040\t] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] )* \) )* \) )* \. # if led by a period... (?: [\040\t] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] )* \) )* \) )* (?: [^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+ # some number of atom characters... (?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom | \[ # [ (?: [^\\\x80-\xff\n\015\[\]] | \\ [^\x80-\xff] )* # stuff \] # ] ) # ...further okay )* # address | # or (?: [^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+ # some number of atom characters... (?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom | " (?: # opening quote... [^\\\x80-\xff\n\015"] # Anything except backslash and quote | # or \\ [^\x80-\xff] # Escaped something (something != CR) )* " # closing quote ) # one word, optionally followed by.... (?: [^()<>@,;:".\\\[\]\x80-\xff\000-\010\012-\037] | # atom and space parts, or... \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] )* \) )* \) | # comments, or... " (?: # opening quote... [^\\\x80-\xff\n\015"] # Anything except backslash and quote | # or \\ [^\x80-\xff] # Escaped something (something != CR) )* " # closing quote # quoted strings )* < (?: [\040\t] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] )* \) )* \) )* # leading < (?: @ (?: [\040\t] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] )* \) )* \) )* (?: [^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+ # some number of atom characters... (?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom | \[ # [ (?: [^\\\x80-\xff\n\015\[\]] | \\ [^\x80-\xff] )* # stuff \] # ] ) # initial subdomain (?: # (?: [\040\t] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] )* \) )* \) )* \. # if led by a period... (?: [\040\t] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] )* \) )* \) )* (?: [^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+ # some number of atom characters... (?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom | \[ # [ (?: [^\\\x80-\xff\n\015\[\]] | \\ [^\x80-\xff] )* # stuff \] # ] ) # ...further okay )* (?: (?: [\040\t] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] )* \) )* \) )* , (?: [\040\t] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] )* \) )* \) )* @ (?: [\040\t] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] )* \) )* \) )* (?: [^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+ # some number of atom characters... (?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom | \[ # [ (?: [^\\\x80-\xff\n\015\[\]] | \\ [^\x80-\xff] )* # stuff \] # ] ) # initial subdomain (?: # (?: [\040\t] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] )* \) )* \) )* \. # if led by a period... (?: [\040\t] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] )* \) )* \) )* (?: [^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+ # some number of atom characters... (?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom | \[ # [ (?: [^\\\x80-\xff\n\015\[\]] | \\ [^\x80-\xff] )* # stuff \] # ] ) # ...further okay )* )* # further okay, if led by comma : # closing colon (?: [\040\t] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] )* \) )* \) )* )? # optional route (?: [^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+ # some number of atom characters... (?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom | " (?: # opening quote... [^\\\x80-\xff\n\015"] # Anything except backslash and quote | # or \\ [^\x80-\xff] # Escaped something (something != CR) )* " # closing quote ) # initial word (?: (?: [\040\t] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] )* \) )* \) )* \. (?: [\040\t] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] )* \) )* \) )* (?: [^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+ # some number of atom characters... (?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom | " (?: # opening quote... [^\\\x80-\xff\n\015"] # Anything except backslash and quote | # or \\ [^\x80-\xff] # Escaped something (something != CR) )* " # closing quote ) )* # further okay, if led by a period (?: [\040\t] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] )* \) )* \) )* @ (?: [\040\t] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] )* \) )* \) )* (?: [^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+ # some number of atom characters... (?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom | \[ # [ (?: [^\\\x80-\xff\n\015\[\]] | \\ [^\x80-\xff] )* # stuff \] # ] ) # initial subdomain (?: # (?: [\040\t] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] )* \) )* \) )* \. # if led by a period... (?: [\040\t] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] )* \) )* \) )* (?: [^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+ # some number of atom characters... (?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom | \[ # [ (?: [^\\\x80-\xff\n\015\[\]] | \\ [^\x80-\xff] )* # stuff \] # ] ) # ...further okay )* # address spec (?: [\040\t] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] )* \) )* \) )* > # trailing > # name and address ) (?: [\040\t] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] | \( (?: [^\\\x80-\xff\n\015()] | \\ [^\x80-\xff] )* \) )* \) )* # optional trailing comment /x Alan Other 0: Alan Other 0: user@dom.ain user\@dom.ain 0: user@dom.ain \"A. Other\" (a comment) 0: "A. Other" (a comment) A. Other (a comment) 0: Other (a comment) \"/s=user/ou=host/o=place/prmd=uu.yy/admd= /c=gb/\"\@x400-re.lay 0: "/s=user/ou=host/o=place/prmd=uu.yy/admd= /c=gb/"@x400-re.lay A missing angle @,;:".\\\[\]\000-\037\x80-\xff]+ # some number of atom characters... (?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom # Atom | # or " # " [^\\\x80-\xff\n\015"] * # normal (?: \\ [^\x80-\xff] [^\\\x80-\xff\n\015"] * )* # ( special normal* )* " # " # Quoted string ) [\040\t]* # Nab whitespace. (?: \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: # ( (?: \\ [^\x80-\xff] | \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: \\ [^\x80-\xff] [^\\\x80-\xff\n\015()] * )* # (special normal*)* \) # ) ) # special [^\\\x80-\xff\n\015()] * # normal* )* # )* \) # ) [\040\t]* )* # If comment found, allow more spaces. (?: \. [\040\t]* # Nab whitespace. (?: \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: # ( (?: \\ [^\x80-\xff] | \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: \\ [^\x80-\xff] [^\\\x80-\xff\n\015()] * )* # (special normal*)* \) # ) ) # special [^\\\x80-\xff\n\015()] * # normal* )* # )* \) # ) [\040\t]* )* # If comment found, allow more spaces. (?: [^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+ # some number of atom characters... (?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom # Atom | # or " # " [^\\\x80-\xff\n\015"] * # normal (?: \\ [^\x80-\xff] [^\\\x80-\xff\n\015"] * )* # ( special normal* )* " # " # Quoted string ) [\040\t]* # Nab whitespace. (?: \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: # ( (?: \\ [^\x80-\xff] | \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: \\ [^\x80-\xff] [^\\\x80-\xff\n\015()] * )* # (special normal*)* \) # ) ) # special [^\\\x80-\xff\n\015()] * # normal* )* # )* \) # ) [\040\t]* )* # If comment found, allow more spaces. # additional words )* @ [\040\t]* # Nab whitespace. (?: \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: # ( (?: \\ [^\x80-\xff] | \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: \\ [^\x80-\xff] [^\\\x80-\xff\n\015()] * )* # (special normal*)* \) # ) ) # special [^\\\x80-\xff\n\015()] * # normal* )* # )* \) # ) [\040\t]* )* # If comment found, allow more spaces. (?: [^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+ # some number of atom characters... (?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom | \[ # [ (?: [^\\\x80-\xff\n\015\[\]] | \\ [^\x80-\xff] )* # stuff \] # ] ) [\040\t]* # Nab whitespace. (?: \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: # ( (?: \\ [^\x80-\xff] | \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: \\ [^\x80-\xff] [^\\\x80-\xff\n\015()] * )* # (special normal*)* \) # ) ) # special [^\\\x80-\xff\n\015()] * # normal* )* # )* \) # ) [\040\t]* )* # If comment found, allow more spaces. # optional trailing comments (?: \. [\040\t]* # Nab whitespace. (?: \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: # ( (?: \\ [^\x80-\xff] | \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: \\ [^\x80-\xff] [^\\\x80-\xff\n\015()] * )* # (special normal*)* \) # ) ) # special [^\\\x80-\xff\n\015()] * # normal* )* # )* \) # ) [\040\t]* )* # If comment found, allow more spaces. (?: [^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+ # some number of atom characters... (?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom | \[ # [ (?: [^\\\x80-\xff\n\015\[\]] | \\ [^\x80-\xff] )* # stuff \] # ] ) [\040\t]* # Nab whitespace. (?: \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: # ( (?: \\ [^\x80-\xff] | \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: \\ [^\x80-\xff] [^\\\x80-\xff\n\015()] * )* # (special normal*)* \) # ) ) # special [^\\\x80-\xff\n\015()] * # normal* )* # )* \) # ) [\040\t]* )* # If comment found, allow more spaces. # optional trailing comments )* # address | # or (?: [^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+ # some number of atom characters... (?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom # Atom | # or " # " [^\\\x80-\xff\n\015"] * # normal (?: \\ [^\x80-\xff] [^\\\x80-\xff\n\015"] * )* # ( special normal* )* " # " # Quoted string ) # leading word [^()<>@,;:".\\\[\]\x80-\xff\000-\010\012-\037] * # "normal" atoms and or spaces (?: (?: \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: # ( (?: \\ [^\x80-\xff] | \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: \\ [^\x80-\xff] [^\\\x80-\xff\n\015()] * )* # (special normal*)* \) # ) ) # special [^\\\x80-\xff\n\015()] * # normal* )* # )* \) # ) | " # " [^\\\x80-\xff\n\015"] * # normal (?: \\ [^\x80-\xff] [^\\\x80-\xff\n\015"] * )* # ( special normal* )* " # " ) # "special" comment or quoted string [^()<>@,;:".\\\[\]\x80-\xff\000-\010\012-\037] * # more "normal" )* < [\040\t]* # Nab whitespace. (?: \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: # ( (?: \\ [^\x80-\xff] | \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: \\ [^\x80-\xff] [^\\\x80-\xff\n\015()] * )* # (special normal*)* \) # ) ) # special [^\\\x80-\xff\n\015()] * # normal* )* # )* \) # ) [\040\t]* )* # If comment found, allow more spaces. # < (?: @ [\040\t]* # Nab whitespace. (?: \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: # ( (?: \\ [^\x80-\xff] | \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: \\ [^\x80-\xff] [^\\\x80-\xff\n\015()] * )* # (special normal*)* \) # ) ) # special [^\\\x80-\xff\n\015()] * # normal* )* # )* \) # ) [\040\t]* )* # If comment found, allow more spaces. (?: [^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+ # some number of atom characters... (?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom | \[ # [ (?: [^\\\x80-\xff\n\015\[\]] | \\ [^\x80-\xff] )* # stuff \] # ] ) [\040\t]* # Nab whitespace. (?: \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: # ( (?: \\ [^\x80-\xff] | \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: \\ [^\x80-\xff] [^\\\x80-\xff\n\015()] * )* # (special normal*)* \) # ) ) # special [^\\\x80-\xff\n\015()] * # normal* )* # )* \) # ) [\040\t]* )* # If comment found, allow more spaces. # optional trailing comments (?: \. [\040\t]* # Nab whitespace. (?: \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: # ( (?: \\ [^\x80-\xff] | \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: \\ [^\x80-\xff] [^\\\x80-\xff\n\015()] * )* # (special normal*)* \) # ) ) # special [^\\\x80-\xff\n\015()] * # normal* )* # )* \) # ) [\040\t]* )* # If comment found, allow more spaces. (?: [^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+ # some number of atom characters... (?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom | \[ # [ (?: [^\\\x80-\xff\n\015\[\]] | \\ [^\x80-\xff] )* # stuff \] # ] ) [\040\t]* # Nab whitespace. (?: \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: # ( (?: \\ [^\x80-\xff] | \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: \\ [^\x80-\xff] [^\\\x80-\xff\n\015()] * )* # (special normal*)* \) # ) ) # special [^\\\x80-\xff\n\015()] * # normal* )* # )* \) # ) [\040\t]* )* # If comment found, allow more spaces. # optional trailing comments )* (?: , [\040\t]* # Nab whitespace. (?: \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: # ( (?: \\ [^\x80-\xff] | \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: \\ [^\x80-\xff] [^\\\x80-\xff\n\015()] * )* # (special normal*)* \) # ) ) # special [^\\\x80-\xff\n\015()] * # normal* )* # )* \) # ) [\040\t]* )* # If comment found, allow more spaces. @ [\040\t]* # Nab whitespace. (?: \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: # ( (?: \\ [^\x80-\xff] | \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: \\ [^\x80-\xff] [^\\\x80-\xff\n\015()] * )* # (special normal*)* \) # ) ) # special [^\\\x80-\xff\n\015()] * # normal* )* # )* \) # ) [\040\t]* )* # If comment found, allow more spaces. (?: [^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+ # some number of atom characters... (?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom | \[ # [ (?: [^\\\x80-\xff\n\015\[\]] | \\ [^\x80-\xff] )* # stuff \] # ] ) [\040\t]* # Nab whitespace. (?: \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: # ( (?: \\ [^\x80-\xff] | \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: \\ [^\x80-\xff] [^\\\x80-\xff\n\015()] * )* # (special normal*)* \) # ) ) # special [^\\\x80-\xff\n\015()] * # normal* )* # )* \) # ) [\040\t]* )* # If comment found, allow more spaces. # optional trailing comments (?: \. [\040\t]* # Nab whitespace. (?: \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: # ( (?: \\ [^\x80-\xff] | \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: \\ [^\x80-\xff] [^\\\x80-\xff\n\015()] * )* # (special normal*)* \) # ) ) # special [^\\\x80-\xff\n\015()] * # normal* )* # )* \) # ) [\040\t]* )* # If comment found, allow more spaces. (?: [^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+ # some number of atom characters... (?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom | \[ # [ (?: [^\\\x80-\xff\n\015\[\]] | \\ [^\x80-\xff] )* # stuff \] # ] ) [\040\t]* # Nab whitespace. (?: \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: # ( (?: \\ [^\x80-\xff] | \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: \\ [^\x80-\xff] [^\\\x80-\xff\n\015()] * )* # (special normal*)* \) # ) ) # special [^\\\x80-\xff\n\015()] * # normal* )* # )* \) # ) [\040\t]* )* # If comment found, allow more spaces. # optional trailing comments )* )* # additional domains : [\040\t]* # Nab whitespace. (?: \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: # ( (?: \\ [^\x80-\xff] | \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: \\ [^\x80-\xff] [^\\\x80-\xff\n\015()] * )* # (special normal*)* \) # ) ) # special [^\\\x80-\xff\n\015()] * # normal* )* # )* \) # ) [\040\t]* )* # If comment found, allow more spaces. # optional trailing comments )? # optional route (?: [^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+ # some number of atom characters... (?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom # Atom | # or " # " [^\\\x80-\xff\n\015"] * # normal (?: \\ [^\x80-\xff] [^\\\x80-\xff\n\015"] * )* # ( special normal* )* " # " # Quoted string ) [\040\t]* # Nab whitespace. (?: \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: # ( (?: \\ [^\x80-\xff] | \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: \\ [^\x80-\xff] [^\\\x80-\xff\n\015()] * )* # (special normal*)* \) # ) ) # special [^\\\x80-\xff\n\015()] * # normal* )* # )* \) # ) [\040\t]* )* # If comment found, allow more spaces. (?: \. [\040\t]* # Nab whitespace. (?: \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: # ( (?: \\ [^\x80-\xff] | \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: \\ [^\x80-\xff] [^\\\x80-\xff\n\015()] * )* # (special normal*)* \) # ) ) # special [^\\\x80-\xff\n\015()] * # normal* )* # )* \) # ) [\040\t]* )* # If comment found, allow more spaces. (?: [^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+ # some number of atom characters... (?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom # Atom | # or " # " [^\\\x80-\xff\n\015"] * # normal (?: \\ [^\x80-\xff] [^\\\x80-\xff\n\015"] * )* # ( special normal* )* " # " # Quoted string ) [\040\t]* # Nab whitespace. (?: \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: # ( (?: \\ [^\x80-\xff] | \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: \\ [^\x80-\xff] [^\\\x80-\xff\n\015()] * )* # (special normal*)* \) # ) ) # special [^\\\x80-\xff\n\015()] * # normal* )* # )* \) # ) [\040\t]* )* # If comment found, allow more spaces. # additional words )* @ [\040\t]* # Nab whitespace. (?: \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: # ( (?: \\ [^\x80-\xff] | \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: \\ [^\x80-\xff] [^\\\x80-\xff\n\015()] * )* # (special normal*)* \) # ) ) # special [^\\\x80-\xff\n\015()] * # normal* )* # )* \) # ) [\040\t]* )* # If comment found, allow more spaces. (?: [^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+ # some number of atom characters... (?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom | \[ # [ (?: [^\\\x80-\xff\n\015\[\]] | \\ [^\x80-\xff] )* # stuff \] # ] ) [\040\t]* # Nab whitespace. (?: \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: # ( (?: \\ [^\x80-\xff] | \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: \\ [^\x80-\xff] [^\\\x80-\xff\n\015()] * )* # (special normal*)* \) # ) ) # special [^\\\x80-\xff\n\015()] * # normal* )* # )* \) # ) [\040\t]* )* # If comment found, allow more spaces. # optional trailing comments (?: \. [\040\t]* # Nab whitespace. (?: \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: # ( (?: \\ [^\x80-\xff] | \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: \\ [^\x80-\xff] [^\\\x80-\xff\n\015()] * )* # (special normal*)* \) # ) ) # special [^\\\x80-\xff\n\015()] * # normal* )* # )* \) # ) [\040\t]* )* # If comment found, allow more spaces. (?: [^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+ # some number of atom characters... (?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]) # ..not followed by something that could be part of an atom | \[ # [ (?: [^\\\x80-\xff\n\015\[\]] | \\ [^\x80-\xff] )* # stuff \] # ] ) [\040\t]* # Nab whitespace. (?: \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: # ( (?: \\ [^\x80-\xff] | \( # ( [^\\\x80-\xff\n\015()] * # normal* (?: \\ [^\x80-\xff] [^\\\x80-\xff\n\015()] * )* # (special normal*)* \) # ) ) # special [^\\\x80-\xff\n\015()] * # normal* )* # )* \) # ) [\040\t]* )* # If comment found, allow more spaces. # optional trailing comments )* # address spec > # > # name and address ) /x Alan Other 0: Alan Other 0: user@dom.ain user\@dom.ain 0: user@dom.ain \"A. Other\" (a comment) 0: "A. Other" A. Other (a comment) 0: Other \"/s=user/ou=host/o=place/prmd=uu.yy/admd= /c=gb/\"\@x400-re.lay 0: "/s=user/ou=host/o=place/prmd=uu.yy/admd= /c=gb/"@x400-re.lay A missing angle ?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~\x7f\x80\x81\x82\x83\x84\x85\x86\x87\x88\x89\x8a\x8b\x8c\x8d\x8e\x8f\x90\x91\x92\x93\x94\x95\x96\x97\x98\x99\x9a\x9b\x9c\x9d\x9e\x9f\xa0\xa1\xa2\xa3\xa4\xa5\xa6\xa7\xa8\xa9\xaa\xab\xac\xad\xae\xaf\xb0\xb1\xb2\xb3\xb4\xb5\xb6\xb7\xb8\xb9\xba\xbb\xbc\xbd\xbe\xbf\xc0\xc1\xc2\xc3\xc4\xc5\xc6\xc7\xc8\xc9\xca\xcb\xcc\xcd\xce\xcf\xd0\xd1\xd2\xd3\xd4\xd5\xd6\xd7\xd8\xd9\xda\xdb\xdc\xdd\xde\xdf\xe0\xe1\xe2\xe3\xe4\xe5\xe6\xe7\xe8\xe9\xea\xeb\xec\xed\xee\xef\xf0\xf1\xf2\xf3\xf4\xf5\xf6\xf7\xf8\xf9\xfa\xfb\xfc\xfd\xfe\xff /P[^*]TAIRE[^*]{1,6}?LL/ xxxxxxxxxxxPSTAIREISLLxxxxxxxxx 0: PSTAIREISLL /P[^*]TAIRE[^*]{1,}?LL/ xxxxxxxxxxxPSTAIREISLLxxxxxxxxx 0: PSTAIREISLL /(\.\d\d[1-9]?)\d+/ 1.230003938 0: .230003938 1: .23 1.875000282 0: .875000282 1: .875 1.235 0: .235 1: .23 /(\.\d\d((?=0)|\d(?=\d)))/ 1.230003938 0: .23 1: .23 2: 1.875000282 0: .875 1: .875 2: 5 *** Failers No match 1.235 No match /a(?)b/ ab 0: ab /\b(foo)\s+(\w+)/i Food is on the foo table 0: foo table 1: foo 2: table /foo(.*)bar/ The food is under the bar in the barn. 0: food is under the bar in the bar 1: d is under the bar in the /foo(.*?)bar/ The food is under the bar in the barn. 0: food is under the bar 1: d is under the /(.*)(\d*)/ I have 2 numbers: 53147 0: I have 2 numbers: 53147 1: I have 2 numbers: 53147 2: /(.*)(\d+)/ I have 2 numbers: 53147 0: I have 2 numbers: 53147 1: I have 2 numbers: 5314 2: 7 /(.*?)(\d*)/ I have 2 numbers: 53147 0: 1: 2: /(.*?)(\d+)/ I have 2 numbers: 53147 0: I have 2 1: I have 2: 2 /(.*)(\d+)$/ I have 2 numbers: 53147 0: I have 2 numbers: 53147 1: I have 2 numbers: 5314 2: 7 /(.*?)(\d+)$/ I have 2 numbers: 53147 0: I have 2 numbers: 53147 1: I have 2 numbers: 2: 53147 /(.*)\b(\d+)$/ I have 2 numbers: 53147 0: I have 2 numbers: 53147 1: I have 2 numbers: 2: 53147 /(.*\D)(\d+)$/ I have 2 numbers: 53147 0: I have 2 numbers: 53147 1: I have 2 numbers: 2: 53147 /^\D*(?!123)/ ABC123 0: AB /^(\D*)(?=\d)(?!123)/ ABC445 0: ABC 1: ABC *** Failers No match ABC123 No match /^[W-]46]/ W46]789 0: W46] -46]789 0: -46] *** Failers No match Wall No match Zebra No match 42 No match [abcd] No match ]abcd[ No match /^[W-\]46]/ W46]789 0: W Wall 0: W Zebra 0: Z Xylophone 0: X 42 0: 4 [abcd] 0: [ ]abcd[ 0: ] \\backslash 0: \ *** Failers No match -46]789 No match well No match /\d\d\/\d\d\/\d\d\d\d/ 01/01/2000 0: 01/01/2000 /word (?:[a-zA-Z0-9]+ ){0,10}otherword/ word cat dog elephant mussel cow horse canary baboon snake shark otherword 0: word cat dog elephant mussel cow horse canary baboon snake shark otherword word cat dog elephant mussel cow horse canary baboon snake shark No match /word (?:[a-zA-Z0-9]+ ){0,300}otherword/ word cat dog elephant mussel cow horse canary baboon snake shark the quick brown fox and the lazy dog and several other words getting close to thirty by now I hope No match /^(a){0,0}/ bcd 0: abc 0: aab 0: /^(a){0,1}/ bcd 0: abc 0: a 1: a aab 0: a 1: a /^(a){0,2}/ bcd 0: abc 0: a 1: a aab 0: aa 1: a /^(a){0,3}/ bcd 0: abc 0: a 1: a aab 0: aa 1: a aaa 0: aaa 1: a /^(a){0,}/ bcd 0: abc 0: a 1: a aab 0: aa 1: a aaa 0: aaa 1: a aaaaaaaa 0: aaaaaaaa 1: a /^(a){1,1}/ bcd No match abc 0: a 1: a aab 0: a 1: a /^(a){1,2}/ bcd No match abc 0: a 1: a aab 0: aa 1: a /^(a){1,3}/ bcd No match abc 0: a 1: a aab 0: aa 1: a aaa 0: aaa 1: a /^(a){1,}/ bcd No match abc 0: a 1: a aab 0: aa 1: a aaa 0: aaa 1: a aaaaaaaa 0: aaaaaaaa 1: a /.*\.gif/ borfle\nbib.gif\nno 0: bib.gif /.{0,}\.gif/ borfle\nbib.gif\nno 0: bib.gif /.*\.gif/m borfle\nbib.gif\nno 0: bib.gif /.*\.gif/s borfle\nbib.gif\nno 0: borfle\x0abib.gif /.*\.gif/ms borfle\nbib.gif\nno 0: borfle\x0abib.gif /.*$/ borfle\nbib.gif\nno 0: no /.*$/m borfle\nbib.gif\nno 0: borfle /.*$/s borfle\nbib.gif\nno 0: borfle\x0abib.gif\x0ano /.*$/ms borfle\nbib.gif\nno 0: borfle\x0abib.gif\x0ano /.*$/ borfle\nbib.gif\nno\n 0: no /.*$/m borfle\nbib.gif\nno\n 0: borfle /.*$/s borfle\nbib.gif\nno\n 0: borfle\x0abib.gif\x0ano\x0a /.*$/ms borfle\nbib.gif\nno\n 0: borfle\x0abib.gif\x0ano\x0a /(.*X|^B)/ abcde\n1234Xyz 0: 1234X 1: 1234X BarFoo 0: B 1: B *** Failers No match abcde\nBar No match /(.*X|^B)/m abcde\n1234Xyz 0: 1234X 1: 1234X BarFoo 0: B 1: B abcde\nBar 0: B 1: B /(.*X|^B)/s abcde\n1234Xyz 0: abcde\x0a1234X 1: abcde\x0a1234X BarFoo 0: B 1: B *** Failers No match abcde\nBar No match /(.*X|^B)/ms abcde\n1234Xyz 0: abcde\x0a1234X 1: abcde\x0a1234X BarFoo 0: B 1: B abcde\nBar 0: B 1: B /(?s)(.*X|^B)/ abcde\n1234Xyz 0: abcde\x0a1234X 1: abcde\x0a1234X BarFoo 0: B 1: B *** Failers No match abcde\nBar No match /(?s:.*X|^B)/ abcde\n1234Xyz 0: abcde\x0a1234X BarFoo 0: B *** Failers No match abcde\nBar No match /^.*B/ **** Failers No match abc\nB No match /(?s)^.*B/ abc\nB 0: abc\x0aB /(?m)^.*B/ abc\nB 0: B /(?ms)^.*B/ abc\nB 0: abc\x0aB /(?ms)^B/ abc\nB 0: B /(?s)B$/ B\n 0: B /^[0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]/ 123456654321 0: 123456654321 /^\d\d\d\d\d\d\d\d\d\d\d\d/ 123456654321 0: 123456654321 /^[\d][\d][\d][\d][\d][\d][\d][\d][\d][\d][\d][\d]/ 123456654321 0: 123456654321 /^[abc]{12}/ abcabcabcabc 0: abcabcabcabc /^[a-c]{12}/ abcabcabcabc 0: abcabcabcabc /^(a|b|c){12}/ abcabcabcabc 0: abcabcabcabc 1: c /^[abcdefghijklmnopqrstuvwxy0123456789]/ n 0: n *** Failers No match z No match /abcde{0,0}/ abcd 0: abcd *** Failers No match abce No match /ab[cd]{0,0}e/ abe 0: abe *** Failers No match abcde No match /ab(c){0,0}d/ abd 0: abd *** Failers No match abcd No match /a(b*)/ a 0: a 1: ab 0: ab 1: b abbbb 0: abbbb 1: bbbb *** Failers 0: a 1: bbbbb No match /ab\d{0}e/ abe 0: abe *** Failers No match ab1e No match /"([^\\"]+|\\.)*"/ the \"quick\" brown fox 0: "quick" 1: quick \"the \\\"quick\\\" brown fox\" 0: "the \"quick\" brown fox" 1: brown fox /.*?/g+ abc 0: 0+ abc 0: a 0+ bc 0: 0+ bc 0: b 0+ c 0: 0+ c 0: c 0+ 0: 0+ /\b/g+ abc 0: 0+ abc 0: 0+ /\b/+g abc 0: 0+ abc 0: 0+ //g abc 0: 0: 0: 0: /]{0,})>]{0,})>([\d]{0,}\.)(.*)((
([\w\W\s\d][^<>]{0,})|[\s]{0,}))<\/a><\/TD>]{0,})>([\w\W\s\d][^<>]{0,})<\/TD>]{0,})>([\w\W\s\d][^<>]{0,})<\/TD><\/TR>/is 43.Word Processor
(N-1286)Lega lstaff.comCA - Statewide 0: 43.Word Processor
(N-1286)Lega lstaff.comCA - Statewide 1: BGCOLOR='#DBE9E9' 2: align=left valign=top 3: 43. 4: Word Processor
(N-1286) 5: 6: 7: 8: align=left valign=top 9: Lega lstaff.com 10: align=left valign=top 11: CA - Statewide /a[^a]b/ acb 0: acb a\nb 0: a\x0ab /a.b/ acb 0: acb *** Failers No match a\nb No match /a[^a]b/s acb 0: acb a\nb 0: a\x0ab /a.b/s acb 0: acb a\nb 0: a\x0ab /^(b+?|a){1,2}?c/ bac 0: bac 1: a bbac 0: bbac 1: a bbbac 0: bbbac 1: a bbbbac 0: bbbbac 1: a bbbbbac 0: bbbbbac 1: a /^(b+|a){1,2}?c/ bac 0: bac 1: a bbac 0: bbac 1: a bbbac 0: bbbac 1: a bbbbac 0: bbbbac 1: a bbbbbac 0: bbbbbac 1: a /(?!\A)x/m x\nb\n No match a\bx\n 0: x /\x0{ab}/ \0{ab} 0: \x00{ab} /(A|B)*?CD/ CD 0: CD /(A|B)*CD/ CD 0: CD /(AB)*?\1/ ABABAB 0: ABAB 1: AB /(AB)*\1/ ABABAB 0: ABABAB 1: AB /(?.*/)foo" /this/is/a/very/long/line/in/deed/with/very/many/slashes/in/it/you/see/ No match "(?>.*/)foo" /this/is/a/very/long/line/in/deed/with/very/many/slashes/in/and/foo 0: /this/is/a/very/long/line/in/deed/with/very/many/slashes/in/and/foo /(?>(\.\d\d[1-9]?))\d+/ 1.230003938 0: .230003938 1: .23 1.875000282 0: .875000282 1: .875 *** Failers No match 1.235 No match /^((?>\w+)|(?>\s+))*$/ now is the time for all good men to come to the aid of the party 0: now is the time for all good men to come to the aid of the party 1: party *** Failers No match this is not a line with only words and spaces! No match /(\d+)(\w)/ 12345a 0: 12345a 1: 12345 2: a 12345+ 0: 12345 1: 1234 2: 5 /((?>\d+))(\w)/ 12345a 0: 12345a 1: 12345 2: a *** Failers No match 12345+ No match /(?>a+)b/ aaab 0: aaab /((?>a+)b)/ aaab 0: aaab 1: aaab /(?>(a+))b/ aaab 0: aaab 1: aaa /(?>b)+/ aaabbbccc 0: bbb /(?>a+|b+|c+)*c/ aaabbbbccccd 0: aaabbbbc /((?>[^()]+)|\([^()]*\))+/ ((abc(ade)ufh()()x 0: abc(ade)ufh()()x 1: x /\(((?>[^()]+)|\([^()]+\))+\)/ (abc) 0: (abc) 1: abc (abc(def)xyz) 0: (abc(def)xyz) 1: xyz *** Failers No match ((()aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa No match /a(?-i)b/i ab 0: ab Ab 0: Ab *** Failers No match aB No match AB No match /(a (?x)b c)d e/ a bcd e 0: a bcd e 1: a bc *** Failers No match a b cd e No match abcd e No match a bcde No match /(a b(?x)c d (?-x)e f)/ a bcde f 0: a bcde f 1: a bcde f *** Failers No match abcdef No match /(a(?i)b)c/ abc 0: abc 1: ab aBc 0: aBc 1: aB *** Failers No match abC No match aBC No match Abc No match ABc No match ABC No match AbC No match /a(?i:b)c/ abc 0: abc aBc 0: aBc *** Failers No match ABC No match abC No match aBC No match /a(?i:b)*c/ aBc 0: aBc aBBc 0: aBBc *** Failers No match aBC No match aBBC No match /a(?=b(?i)c)\w\wd/ abcd 0: abcd abCd 0: abCd *** Failers No match aBCd No match abcD No match /(?s-i:more.*than).*million/i more than million 0: more than million more than MILLION 0: more than MILLION more \n than Million 0: more \x0a than Million *** Failers No match MORE THAN MILLION No match more \n than \n million No match /(?:(?s-i)more.*than).*million/i more than million 0: more than million more than MILLION 0: more than MILLION more \n than Million 0: more \x0a than Million *** Failers No match MORE THAN MILLION No match more \n than \n million No match /(?>a(?i)b+)+c/ abc 0: abc aBbc 0: aBbc aBBc 0: aBBc *** Failers No match Abc No match abAb No match abbC No match /(?=a(?i)b)\w\wc/ abc 0: abc aBc 0: aBc *** Failers No match Ab No match abC No match aBC No match /(?<=a(?i)b)(\w\w)c/ abxxc 0: xxc 1: xx aBxxc 0: xxc 1: xx *** Failers No match Abxxc No match ABxxc No match abxxC No match /(?:(a)|b)(?(1)A|B)/ aA 0: aA 1: a bB 0: bB *** Failers No match aB No match bA No match /^(a)?(?(1)a|b)+$/ aa 0: aa 1: a b 0: b bb 0: bb *** Failers No match ab No match /^(?(?=abc)\w{3}:|\d\d)$/ abc: 0: abc: 12 0: 12 *** Failers No match 123 No match xyz No match /^(?(?!abc)\d\d|\w{3}:)$/ abc: 0: abc: 12 0: 12 *** Failers No match 123 No match xyz No match /(?(?<=foo)bar|cat)/ foobar 0: bar cat 0: cat fcat 0: cat focat 0: cat *** Failers No match foocat No match /(?(?a*)*/ a 0: a aa 0: aa aaaa 0: aaaa /(abc|)+/ abc 0: abc 1: abcabc 0: abcabc 1: abcabcabc 0: abcabcabc 1: xyz 0: 1: /([a]*)*/ a 0: a 1: aaaaa 0: aaaaa 1: /([ab]*)*/ a 0: a 1: b 0: b 1: ababab 0: ababab 1: aaaabcde 0: aaaab 1: bbbb 0: bbbb 1: /([^a]*)*/ b 0: b 1: bbbb 0: bbbb 1: aaa 0: 1: /([^ab]*)*/ cccc 0: cccc 1: abab 0: 1: /([a]*?)*/ a 0: 1: aaaa 0: 1: /([ab]*?)*/ a 0: 1: b 0: 1: abab 0: 1: baba 0: 1: /([^a]*?)*/ b 0: 1: bbbb 0: 1: aaa 0: 1: /([^ab]*?)*/ c 0: 1: cccc 0: 1: baba 0: 1: /(?>a*)*/ a 0: a aaabcde 0: aaa /((?>a*))*/ aaaaa 0: aaaaa 1: aabbaa 0: aa 1: /((?>a*?))*/ aaaaa 0: 1: aabbaa 0: 1: /(?(?=[^a-z]+[a-z]) \d{2}-[a-z]{3}-\d{2} | \d{2}-\d{2}-\d{2} ) /x 12-sep-98 0: 12-sep-98 12-09-98 0: 12-09-98 *** Failers No match sep-12-98 No match /(?<=(foo))bar\1/ foobarfoo 0: barfoo 1: foo foobarfootling 0: barfoo 1: foo *** Failers No match foobar No match barfoo No match /(?i:saturday|sunday)/ saturday 0: saturday sunday 0: sunday Saturday 0: Saturday Sunday 0: Sunday SATURDAY 0: SATURDAY SUNDAY 0: SUNDAY SunDay 0: SunDay /(a(?i)bc|BB)x/ abcx 0: abcx 1: abc aBCx 0: aBCx 1: aBC bbx 0: bbx 1: bb BBx 0: BBx 1: BB *** Failers No match abcX No match aBCX No match bbX No match BBX No match /^([ab](?i)[cd]|[ef])/ ac 0: ac 1: ac aC 0: aC 1: aC bD 0: bD 1: bD elephant 0: e 1: e Europe 0: E 1: E frog 0: f 1: f France 0: F 1: F *** Failers No match Africa No match /^(ab|a(?i)[b-c](?m-i)d|x(?i)y|z)/ ab 0: ab 1: ab aBd 0: aBd 1: aBd xy 0: xy 1: xy xY 0: xY 1: xY zebra 0: z 1: z Zambesi 0: Z 1: Z *** Failers No match aCD No match XY No match /(?<=foo\n)^bar/m foo\nbar 0: bar *** Failers No match bar No match baz\nbar No match /(?<=(?]&/ <&OUT 0: <& /^(a\1?){4}$/ aaaaaaaaaa 0: aaaaaaaaaa 1: aaaa *** Failers No match AB No match aaaaaaaaa No match aaaaaaaaaaa No match /^(a(?(1)\1)){4}$/ aaaaaaaaaa 0: aaaaaaaaaa 1: aaaa *** Failers No match aaaaaaaaa No match aaaaaaaaaaa No match /(?:(f)(o)(o)|(b)(a)(r))*/ foobar 0: foobar 1: f 2: o 3: o 4: b 5: a 6: r /(?<=a)b/ ab 0: b *** Failers No match cb No match b No match /(? 2: abcd xy:z:::abcd 0: xy:z:::abcd 1: xy:z::: 2: abcd /^[^bcd]*(c+)/ aexycd 0: aexyc 1: c /(a*)b+/ caab 0: aab 1: aa /([\w:]+::)?(\w+)$/ abcd 0: abcd 1: 2: abcd xy:z:::abcd 0: xy:z:::abcd 1: xy:z::: 2: abcd *** Failers 0: Failers 1: 2: Failers abcd: No match abcd: No match /^[^bcd]*(c+)/ aexycd 0: aexyc 1: c /(>a+)ab/ /(?>a+)b/ aaab 0: aaab /([[:]+)/ a:[b]: 0: :[ 1: :[ /([[=]+)/ a=[b]= 0: =[ 1: =[ /([[.]+)/ a.[b]. 0: .[ 1: .[ /((?>a+)b)/ aaab 0: aaab 1: aaab /(?>(a+))b/ aaab 0: aaab 1: aaa /((?>[^()]+)|\([^()]*\))+/ ((abc(ade)ufh()()x 0: abc(ade)ufh()()x 1: x /a\Z/ *** Failers No match aaab No match a\nb\n No match /b\Z/ a\nb\n 0: b /b\z/ /b\Z/ a\nb 0: b /b\z/ a\nb 0: b *** Failers No match /^(?>(?(1)\.|())[^\W_](?>[a-z0-9-]*[^\W_])?)+$/ a 0: a 1: abc 0: abc 1: a-b 0: a-b 1: 0-9 0: 0-9 1: a.b 0: a.b 1: 5.6.7 0: 5.6.7 1: the.quick.brown.fox 0: the.quick.brown.fox 1: a100.b200.300c 0: a100.b200.300c 1: 12-ab.1245 0: 12-ab.1245 1: *** Failers No match \ No match .a No match -a No match a- No match a. No match a_b No match a.- No match a.. No match ab..bc No match the.quick.brown.fox- No match the.quick.brown.fox. No match the.quick.brown.fox_ No match the.quick.brown.fox+ No match /(?>.*)(?<=(abcd|wxyz))/ alphabetabcd 0: alphabetabcd 1: abcd endingwxyz 0: endingwxyz 1: wxyz *** Failers No match a rather long string that doesn't end with one of them No match /word (?>(?:(?!otherword)[a-zA-Z0-9]+ ){0,30})otherword/ word cat dog elephant mussel cow horse canary baboon snake shark otherword 0: word cat dog elephant mussel cow horse canary baboon snake shark otherword word cat dog elephant mussel cow horse canary baboon snake shark No match /word (?>[a-zA-Z0-9]+ ){0,30}otherword/ word cat dog elephant mussel cow horse canary baboon snake shark the quick brown fox and the lazy dog and several other words getting close to thirty by now I hope No match /(?<=\d{3}(?!999))foo/ 999foo 0: foo 123999foo 0: foo *** Failers No match 123abcfoo No match /(?<=(?!...999)\d{3})foo/ 999foo 0: foo 123999foo 0: foo *** Failers No match 123abcfoo No match /(?<=\d{3}(?!999)...)foo/ 123abcfoo 0: foo 123456foo 0: foo *** Failers No match 123999foo No match /(?<=\d{3}...)(? 2: 3: abcd 2: 3: abcd \s*)=(?>\s*) # find 2: 3: abcd Z)+|A)*/ ZABCDEFG 0: ZA 1: A /((?>)+|A)*/ ZABCDEFG 0: 1: /a*/g abbab 0: a 0: 0: 0: a 0: 0: /^[a-\d]/ abcde 0: a -things 0: - 0digit 0: 0 *** Failers No match bcdef No match /^[\d-a]/ abcde 0: a -things 0: - 0digit 0: 0 *** Failers No match bcdef No match /[[:space:]]+/ > \x09\x0a\x0c\x0d\x0b< 0: \x09\x0a\x0c\x0d\x0b /[[:blank:]]+/ > \x09\x0a\x0c\x0d\x0b< 0: \x09 /[\s]+/ > \x09\x0a\x0c\x0d\x0b< 0: \x09\x0a\x0c\x0d /\s+/ > \x09\x0a\x0c\x0d\x0b< 0: \x09\x0a\x0c\x0d /a b/x ab No match /(?!\A)x/m a\nxb\n 0: x /(?!^)x/m a\nxb\n No match /abc\Qabc\Eabc/ abcabcabc 0: abcabcabc /abc\Q(*+|\Eabc/ abc(*+|abc 0: abc(*+|abc / abc\Q abc\Eabc/x abc abcabc 0: abc abcabc *** Failers No match abcabcabc No match /abc#comment \Q#not comment literal\E/x abc#not comment\n literal 0: abc#not comment\x0a literal /abc#comment \Q#not comment literal/x abc#not comment\n literal 0: abc#not comment\x0a literal /abc#comment \Q#not comment literal\E #more comment /x abc#not comment\n literal 0: abc#not comment\x0a literal /abc#comment \Q#not comment literal\E #more comment/x abc#not comment\n literal 0: abc#not comment\x0a literal /\Qabc\$xyz\E/ abc\\\$xyz 0: abc\$xyz /\Qabc\E\$\Qxyz\E/ abc\$xyz 0: abc$xyz /\Gabc/ abc 0: abc *** Failers No match xyzabc No match /\Gabc./g abc1abc2xyzabc3 0: abc1 0: abc2 /abc./g abc1abc2xyzabc3 0: abc1 0: abc2 0: abc3 /a(?x: b c )d/ XabcdY 0: abcd *** Failers No match Xa b c d Y No match /((?x)x y z | a b c)/ XabcY 0: abc 1: abc AxyzB 0: xyz 1: xyz /(?i)AB(?-i)C/ XabCY 0: abC *** Failers No match XabcY No match /((?i)AB(?-i)C|D)E/ abCE 0: abCE 1: abC DE 0: DE 1: D *** Failers No match abcE No match abCe No match dE No match De No match /(.*)\d+\1/ abc123abc 0: abc123abc 1: abc abc123bc 0: bc123bc 1: bc /(.*)\d+\1/s abc123abc 0: abc123abc 1: abc abc123bc 0: bc123bc 1: bc /((.*))\d+\1/ abc123abc 0: abc123abc 1: abc 2: abc abc123bc 0: bc123bc 1: bc 2: bc /-- This tests for an IPv6 address in the form where it can have up to --/ /-- eight components, one and only one of which is empty. This must be --/ No match /-- an internal component. --/ No match /^(?!:) # 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 /xi a123::a123 0: a123::a123 1: a123:b342::abcd 0: a123:b342::abcd 1: a123:b342::324e:abcd 0: a123:b342::324e:abcd 1: a123:ddde:b342::324e:abcd 0: a123:ddde:b342::324e:abcd 1: a123:ddde:b342::324e:dcba:abcd 0: a123:ddde:b342::324e:dcba:abcd 1: a123:ddde:9999:b342::324e:dcba:abcd 0: a123:ddde:9999:b342::324e:dcba:abcd 1: *** Failers No match 1:2:3:4:5:6:7:8 No match a123:bce:ddde:9999:b342::324e:dcba:abcd No match a123::9999:b342::324e:dcba:abcd No match abcde:2:3:4:5:6:7:8 No match ::1 No match abcd:fee0:123:: No match :1 No match 1: No match /[z\Qa-d]\E]/ z 0: z a 0: a - 0: - d 0: d ] 0: ] *** Failers 0: a b No match /[\z\C]/ z 0: z C 0: C /\M/ M 0: M /(a+)*b/ aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa No match /(?i)reg(?:ul(?:[a]|ae)r|ex)/ REGular 0: REGular regulaer 0: regulaer Regex 0: Regex regulr 0: regul\xe4r /[--]+/ 0: \xc5\xe6\xe5\xe4\xe0 0: \xc5\xe6\xe5\xe4\xff 0: \xc5\xe6\xe5\xe4\xc0 0: \xc5\xe6\xe5\xe4\xdf /(?<=Z)X./ \x84XAZXB 0: XB /ab cd (?x) de fg/ ab cd defg 0: ab cd defg /ab cd(?x) de fg/ ab cddefg 0: ab cddefg ** Failers No match abcddefg No match /(? 2: D 0: D 1: 2: /(a|)*\d/ aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa No match aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa4 0: aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa4 1: /(?>a|)*\d/ aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa No match aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa4 0: aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa4 /(?:a|)*\d/ aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa No match aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa4 0: aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa4 /\Z/g abc\n 0: 0: /^(?s)(?>.*)(?