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

/
/
gmiu

Test String

Code Generator

Language

Generated Code

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r"^([1-9][0-9]*(?:-[1-9][0-9]*)*)[\s,-]+(?:(bis|ter|qua)[\s,-]+)?([\w]+[\-\w]*)[\s,]+([-\w].+)$" test_str = ("51 bis rue du 26eme régiment d'infanterie\n" "51 ter rue du 26eme régiment d'infanterie\n" "51,bis,rue du 26eme régiment d'infanterie\n" "51 rue du 26eme régiment d'infanterie\n" "51 rue d'Alençon et son apostrophe\n" "51 rue ,du 26eme régiment d'infanterie avec une virgule qui traine\n" "51 bis contre-allée du tiret dans le type de voie\n" "51 rue équateur avec accent en premier caractère de nom de voie\n" "51- rue du tiret inutile après le chiffre\n" "10-12 rue de l'intervalle de numéros de rue\n" "10-12-14-18 rue de l'intervalle beaucoup trop long\n" "51 bis rue -de ' ; la - ,po-nctuation mise n'importe où\n" "51 bis - rue - du 26eme régiment d'infanterie") matches = re.finditer(regex, test_str, re.MULTILINE | re.IGNORECASE | re.UNICODE) 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