Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
No Match

/
/
xgJm

Test String

Code Generator

Language

Generated Code

use strict; my $str = ' F001-AB12 0221 0234-024F 02AE-02AF 03AB; 03CB; Case map 03B0; 03C5 0308 0301; Case map 03C2; 03C3; Case map 03B0; 03C5 0308 0301 0A1B; Case map ----- Start Table A.1 ----- 03D0; 03B2; Case map 03D1; 03B8; Case map ----- End Table A.1 ----- 03D2; 03C5; Additional folding 03D3; 03CD; Additional folding 00DF; 0073 0073; Case map 037B-037D 037F-0383 038B Hoffman & Blanchet Standards Track [Page 89] RFC 3454 Preparation of Internationalized Strings December 2002 1806; ; Map to nothing 1806; ; Map to nothing 1806; ; Map to nothing 1806; ; Map to nothing F0000-FFFFD 100000-10FFFD F0000 013B; 013C; Case map 013D; 013E; Case map 0080-009F; [CONTROL CHARACTERS] 06DD; ARABIC END OF AYAH 070F; SYRIAC ABBREVIATION MARK 180E; MONGOLIAN VOWEL SEPARATOR 200C; ZERO WIDTH NON-JOINER 200D; ZERO WIDTH JOINER 2028; LINE SEPARATOR 2029; PARAGRAPH SEPARATOR 2060; WORD JOINER 2061; FUNCTION APPLICATION 2062; INVISIBLE TIMES 013F; 0140; Case map 0141; 0142; Case map 0143; 0144; Case map 0145; 0146; Case map 0147; 0148; Case map 0149; 02BC 006E; Case map 014A; 014B; Case map 014C; 014D; Case map '; my $regex = qr/(?'char'[A-F0-9]{4,7})\;(?'replace'.*)(?:\s{1}(?'replace'[A-F0-9]{4,7}))+(?=\s)+(?:\s{1}(?'replace'[A-F0-9]{4,7}))+(?=\s)+(?:\s{1}(?'replace'[A-F0-9]{4,7}))+\;\ (?'comment'.*)(?:\n)| (?'char'[A-F0-9]{4,7})\;(?'replace'.*)(?:\s{1}(?'replace'[A-F0-9]{4,7}))+(?=\s)+(?:\s{1}(?'replace'[A-F0-9]{4,7}))+\;\ (?'comment'.*)(?:\n)| (?'char'[A-F0-9]{4,7})\;(?:\s{1}(?'replace'[A-F0-9]{4,7}))+(?=\s)+(?:\s{1}(?'replace'[A-F0-9]{4,7}))+\;\ (?'comment'.*)(?:\n)| (?'char'[A-F0-9]{4,7})\;(?'replace'.*)\;\ (?'comment'.*)(?:\n)| (?'range_start'[A-F0-9]{4,7})\-(?'range_end'[A-F0-9]{4,7})(?:\;\ )(?'comment'.*)(?:\n)| (?'char'[A-F0-9]{4,7})(?:\;\ )(?'comment'.*)(?:\n)| (?'range_start'[A-F0-9]{4,7})\-(?'range_end'[A-F0-9]{4,7})(?:\n)| (?:^\ {3})(?'char'[A-F0-9]{4,7})(?:\n)| (?<appendix>(?'appendix_type'Start|End)\sTable\s(?'appendix_number'(\w).(?'appendix_order'(\d)))(?=\ -----\n))/xmp; if ( $str =~ /$regex/g ) { print "Whole match is ${^MATCH} and its start/end positions can be obtained via \$-[0] and \$+[0]\n"; # print "Capture Group 1 is $1 and its start/end positions can be obtained via \$-[1] and \$+[1]\n"; # print "Capture Group 2 is $2 ... and so on\n"; } # ${^POSTMATCH} and ${^PREMATCH} are also available with the use of '/p' # Named capture groups can be called via $+{name}

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Perl, please visit: http://perldoc.perl.org/perlre.html