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

/
/
ig

Test String

Code Generator

Generated Code

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r"\[?(new|evo|bug|wf)(?:[^0-9]{0,5}(?<!op)(?<!op )([0-9]{5,}))? ?-?_?\|?\]? ?" test_str = ("EVO156484 - ajout avec solde PRI (O/N)\n" "EVO158604 - [GC] Ajout gestion type transport hors moisson\n" "Evo158595 [676M] - OP19068 Integration factures Immo et\n" "Evo158595 [676M] - OP 19068 Integration factures Immo et\n" "Evo OP19068 Integration factures Immo et\n" "Evo OP 19068 Integration factures Immo et\n" "158595 - 676M - OP19068 Integration factures Immo et creat\n" "BUG 160585 Interdire la saisie des temps sur le mois après\n" "BUG-[DSN] Implementation bloc 42 pour CVAE\n" "BUG153922-[DSN] Resolution pb bloc signataire/creation\n" "BUGXXXXXX - [GC] passer entete.zon-int-4 a 0\n" "BUG159220 - En MODEXP si modif Mode reg et mt reg ne\n" "BUG - Ensi 159220 et\n" "Bug888888 - [EMI] retouche pour le window.close\n" "BUG159417 - [GC][MNT157789] Correction controle phyto saisi\n" "[DSN][GRH][WF160820] PB sur les libelles des Types et codes\n" "Evo157633 - 560- OP19043 - Mise à disposition d'une extract\n" "Evo157633 - 560 - OP19043 - Extraction complete de mouvemen\n" "BUG|159471|Calcul des % d'avancement totaux facture dièses\n" "160112 TDB3 ajout diese 52 et 53 reste a receptionner et su\n" "BUG156820 #43 du type port avec enlevement client chargé qu\n" "BUG156820_#43 du type port avec enlevement client chargé qu\n" "BUG 153322suite L'engagé est un BTE composé des CDF non réc") matches = re.finditer(regex, test_str, re.IGNORECASE) for matchNum, match in enumerate(matches, start=1): print ("Match {matchNum} was found at {start}-{end}: {match}".format(matchNum = matchNum, start = match.start(), end = match.end(), match = match.group())) for groupNum in range(0, len(match.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = match.start(groupNum), end = match.end(groupNum), group = match.group(groupNum))) # Note: for Python 2.7 compatibility, use ur"" to prefix the regex and u"" to prefix the test string and substitution.

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 Python, please visit: https://docs.python.org/3/library/re.html