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

Language

Generated Code

const regex = /(^.*?((?:[A-Za-z]+_)+[A-Z]\w+)(?:-([0-9]{8}-[0-9]{6})-([0-9]{8}-[0-9]{6}))?)/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('(^.*?((?:[A-Za-z]+_)+[A-Z]\\w+)(?:-([0-9]{8}-[0-9]{6})-([0-9]{8}-[0-9]{6}))?)', 'gm') const str = `mixexecutor:check_atom_exists:740 - requested to check this machine : ET_colBackDDW_Temp output_of_reports/PII/36478_ABP_BAL_liquidpressure-20210831-123456-20210831-172355.bat.yz packofexecutors:_to_signle_que:869-no mata for file'/private/external_control_time_mapped_low_volume/IBA/54378_BD-RT_69-1-1-20200831-152355-20200831-172355.dat.xz' packofexecutors:_to_signle_que:869-no mata for file'/private/external_control_time_mapped_low_volume/IBA/54378_BD-RT_69-1-20200831-152355-20200831-172355.dat.xz' mixexecutor:check_atom_exists:740 - requested to check this machine : Eanes_colBack12_current packofexecutors._check_tar.587-nr of missed files=78 nr of skipped records=6547 nr of records not exist=0 packofexecutors._filter_mistacl_signals:777 - invalid atomname for RT_6:ESmotormeaninfAmkl`; // 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