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]
  • Character class intersection
    [\w&&[^\d]]
  • 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
Processing...

Test String

Code Generator

Generated Code

const regex = /{{(((?!}}).)*}*}*)}}/g; // Alternative syntax using RegExp constructor // const regex = new RegExp('{{(((?!}}).)*}*}*)}}', 'g') const str = `{{for(var i = 0; i < sites.length; i++) { const site = sites[i]; }} <div class="panel panel-default"> <div class="panel-heading" role="tab"> <h3 class="panel-title"> <a href="#{{site.Nom}}" onclick="event.preventDefault(); toggleOuvertureSite('{{site.Nom}}')" role="button"> {{site.Nom}} <span>({{site.Applications.length}})</span> </a> </h3> </div> <div class="panel-collapse collapse {{if(site.Ouvert){}}in{{}}}" id="{{site.Nom}}"> <div class="panel-body"> <div class="row"> <div class="col-md-6"> <h4>Chemins virtuels</h4> {{if(site.Applications.length == 0) {}} <em>Aucun chemin virtuel</em> {{} else {}} {{for(var j = 0; j < site.Applications.length; j++) { const application = site.Applications[j]; }} <div>{{application.CheminVirtuel}}</div> {{}}}} </div> <div class="col-md-6"> <h4>Liaisons</h4> <table class="table table-condensed"> {{for(var j = 0; j < site.Liaisons.length; j++) { const liaison = site.Liaisons[j]; }} <tr class="row"> <th class="col-xs-6">{{liaison.Protocole}}</th> <td class="col-xs-6">{{liaison.Informations}}</td> </tr> {{}}} </table> </div> </div> </div> </div> </div> {{}}} `; // Reset `lastIndex` if this regex is defined globally // regex.lastIndex = 0; let m; while ((m = regex.exec(str)) !== null) { // This is necessary to avoid infinite loops with zero-width matches if (m.index === regex.lastIndex) { regex.lastIndex++; } // The result can be accessed through the `m`-variable. m.forEach((match, groupIndex) => { console.log(`Found match, group ${groupIndex}: ${match}`); }); }

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