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

/
/
gm

Test String

Code Generator

Language

Generated Code

const regex = /(?<event>^.\S*[^\n<]*(?:(?:<(?!)|\n(?!$))[^\n]*)*(?:|\n$|\z))/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('(?<event>^.\\S*[^\\n<]*(?:(?:<(?!)|\\n(?!$))[^\\n]*)*(?:|\\n$|\\z))', 'gm') const str = `isDraggingObject : True id : afbbdeb7-9fd4-4b53-ab17-742809154ba9 condition : {or, matches System.Object[] (?i)(^.*?host failure alert.*?www\\.jennycraig\\.com\\.au.*?\$), matches System.Object[] (?i)(^.*?\\bwarning\\b.*?www\\.jennycraig\\.com\\.au.*?\$)} catch_all : False advanced_condition : {} actions : {route PVG22KK, severity warning} isDraggingObject : True id : 3b5aa785-b854-4e43-900a-225da5786a27 condition : {or, matches System.Object[] (?i)(^.*?\\bcritical\\b.*?www\\.jennycraig\\.com\\.au.*?\$)} catch_all : False advanced_condition : {} actions : {severity critical, route PVG22KK} **isDraggingObject : True id : a8420998-fbca-486b-9ff7-d03b9e16536e condition : {or, matches System.Object[] (?i)(^.*?\\bcritical\\b.*?www\\.jennycraig\\.com\$), matches System.Object[] (?i)(^.*?\\bcritical\\b.*?locations\\.jennycraig\\.com)} catch_all : False advanced_condition : {} actions : {severity critical, route PW0VV83}**`; // 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