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

Substitution

Processing...

Code Generator

Language

Generated Code

const regex = /,|\((?:[^)(]+|\((?:[^)(]+|\([^)(]*\))*\))*\)/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp(',|\\((?:[^)(]+|\\((?:[^)(]+|\\([^)(]*\\))*\\))*\\)', 'gm') const str = `SELECT TempSynop.Field1 AS Nosta ,CInt(Left([Field2], 4)) AS Tahun ,CInt(Right([Field2], 2)) AS Bulan ,CInt(Left([Field3], 2)) AS Tanggal ,CInt(Mid([Field3], 3, 2)) AS Jam ,Left([Field5], 1) AS NAwan ,CInt(Mid([Field5], 2, 2) "0") AS WDir ,CInt("0" Right([Field5], 2)) AS WSpeed ,Right([Field4], 2) AS Visibility ,Mid([Field12], 2, 2) AS PresentW ,Right([Field12], 2) AS PastW2 ,CInt(Right([Field9], 4)) / 10 AS PSea1 ,IIf([PSea1] < 500, [PSea1] 1000, [PSea1]) AS PSea ,CInt(Right([Field8], 4)) / 10 AS PSta1 ,IIf([PSta1] < 500, [PSta1] 1000, [PSta1]) AS PSta ,CInt(Right([Field6], 3)) / 10 AS TEMP ,CInt(Right([Field7], 3)) / 10 AS DewPoint ,Right([Field11], 4) AS RR2 ,Mid([Field13], 2, 1) AS Nh ,Mid([Field13], 3, 1) AS Cl ,Mid([Field13], 4, 1) AS Cm ,Mid([Field13], 5, 1) AS Ch FROM (SELECT AA, BB, CC FROM TempSynop) ORDER BY TempSynop.Field1; Find all commas that are not in parenthesis. Used in SQL_Pretty_Format() ,|\\((?:[^)(]+|\\((?:[^)(]+|\\([^)(]*\\))*\\))*\\) for vbScript |\$&| ,|\\((?:[^()]++|(?R))*\\) Recursive for AutoHotkey |\$0|`; 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