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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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

r"
"
gm

Test String

Substitution

Processing...

Code Generator

Language

Generated Code

use strict; my $str = '//Bienvenue sur ma carte! //Par Samuel "Déjeuner d\'aujourd\'hui" Lapointe MAP { CONFIG: \'ON_MISSING_DATA\' \'IGNORE\' ##CONFIG: "MS_ERRORFILE" "../debugFile.log" CONFIG: \'PROJ_LIB\' \'../\' FONTSET: \'../fonts.lst\' IMAGETYPE: png MAXSIZE: 4000 SIZE: 800 800 UNITS: meters EXTENT: -20405648.939901 -17712669.979681 20314497.045109 19408951.476421 IMAGECOLOR: \'#C6E2F2\' SHAPEPATH: \'../pdata/natural_earth/\' WEB { METADATA {{ "ows_enable_request" "*" "wms_srs" "EPSG:900913 EPSG:4326 EPSG:3857" "labelcache_map_edge_buffer" "10" "wms_title" "grid" "wms_onlineresource" "http://mapserver.com:8081/cgi-bin/mapserv?map=/opt/scribeui/workspaces/blabla.map" //Un lien! }} IMAGEPATH: \'/tmp/ms_tmp/\' IMAGEURL: \'/ms_tmp/\' } DEBUG: 5 PROJECTION {{ "init=epsg:900913" }} INCLUDE: \'../symbols.map\' }//C\'est la fin! '; my $regex = qr/("(?:\\.|[^"\\])*"|'(?:\\.|[^'\\])*'|(?:[^/\n"']|/[^/*\n"'])+|\n)|(/\* (?:[^*]|\*[^/])*\*/)|(?://(.*)$)$/mp; my $subst = '\\1'; my $result = $str =~ s/$regex/$subst/rg; print "The result of the substitution is' $result\n";

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