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

const regex = new RegExp('("(?:\\\\.|[^"\\\\])*"|\\'(?:\\\\.|[^\\'\\\\])*\\'|(?:[^/\\n"\\']|/[^/*\\n"\\'])+|\\n)|(/\\* (?:[^*]|\\*[^/])*\\*/)|(?://(.*)$)$', 'gm') const 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! `; const subst = `\1`; // The substituted value will be contained in the result variable const result = str.replace(regex, subst); console.log('Substitution result: ', result);

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 JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions