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

/
/
gm

Test String

Substitution

Processing...

Code Generator

Generated Code

const regex = /^( \d|\d\d) /gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('^( \\d|\\d\\d) ', 'gm') const str = ` 1 (function(inDesignMode) { 2 'use strict'; 3 ObjC.import('stdlib'); 4 5 function getPluginParameter(name) { 6 var envName = "KMPARAM_" + name.replace(/ /g, "_"); 7 var result; 8 9 if (!inDesignMode) { 10 result = \$.getenv(envName); 11 return result ? result.trim() : ""; 12 } 13 14 var designingParams = { 15 KMPARAM_Sort_Order: "newest first", 16 KMPARAM_Timestamp_Format: "date + time + duration" 17 }; 18 19 result = designingParams[envName]; 20 if (result === undefined) 21 throw Error("Unknown Plugin Parameter Name '" + name + "' while in designing mode"); 22 return result; 23 } 24 25 function execute() { 26 var sortOrder = getPluginParameter("Sort Order"); 27 var timestampFormat = getPluginParameter("Timestamp Format"); 28 29 return "Sort Order: '" + sortOrder + "'\\nTimestamp Format: '" + timestampFormat + "'"; 30 } 31 32 if (inDesignMode) { 33 return execute(); 34 } else { 35 try { 36 return execute(); 37 } catch (e) { 38 return e.message; 39 } 40 } 41 })(true);`; const subst = ``; // 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