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 = /,{0,1} \w+.(\w+), \w+.(\w+)/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp(',{0,1} \\w+.(\\w+), \\w+.(\\w+)', 'gm') const str = ` v1.VAC_ID, v2.VAC_ID , v1.PAC_ID, v2.PAC_ID , v1.ICL_CPI, v2.ICL_CPI , v1.VAC_TVA, v2.VAC_TVA , v1.TVA_SID, v2.TVA_SID , v1.VAC_DAD, v2.VAC_DAD , v1.VAC_DAD_A, v2.VAC_DAD_A , v1.VAC_DAD_M, v2.VAC_DAD_M , v1.VAC_DAD_H, v2.VAC_DAD_H , v1.VAC_DOS, v2.VAC_DOS , v1.VAC_CPV, v2.VAC_CPV , v1.VAC_TAC, v2.VAC_TAC , v1.VAC_OIN, v2.VAC_OIN , v1.PRO_ID, v2.PRO_ID , v1.RCV_ID, v2.RCV_ID , v1.ID_HORA, v2.ID_HORA , v1.COUNT, v2.COUNT , v1.ASS_SEXE, v2.ASS_SEXE , v1.ASS_DNA, v2.ASS_DNA , v1.ASS_DNA_A, v2.ASS_DNA_A , v1.EDAT, v2.EDAT , v1.UPR_CUP, v2.UPR_CUP , v1.UPR_CUP_T, v2.UPR_CUP_T , v1.PAC_NIA, v2.PAC_NIA , v1.ASS_CSA, v2.ASS_CSA , v1.ICL_UP, v2.ICL_UP , v1.ICL_BAC, v2.ICL_BAC , v1.ICP_UP_ORIGINAL, v2.ICP_UP_ORIGINAL , v1.VAC_DED, v2.VAC_DED , v1.VAC_DED_TRUNC, v2.VAC_DED_TRUNC , v1.ICL_BAD, v2.ICL_BAD , v1.ICL_BAD_TRUNC, v2.ICL_BAD_TRUNC , v1.COUNT_ACTIUS, v2.COUNT_ACTIUS , v1.VAC_LOT, v2.VAC_LOT , v1.VAC_VIA, v2.VAC_VIA , v1.VAC_DCV, v2.VAC_DCV , v1.VAC_LAD, v2.VAC_LAD , v1.VAC_MNV, v2.VAC_MNV , v1.VAC_GPE, v2.VAC_GPE , v1.VAC_GPV, v2.VAC_GPV , v1.VAC_MCO, v2.VAC_MCO , v1.TSI_LOCALITAT, v2.TSI_LOCALITAT , v1.TSI_CPOSTAL, v2.TSI_CPOSTAL , v1.PAC_CIP, v2.PAC_CIP , v1.VAC_DAD_TRUNC, v2.VAC_DAD_TRUNC`; const subst = `or decode(v1.$1, v2.$2, 1, 0) = 0`; // 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