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

r"
"
gm

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"((concorde|immo )?invest\b(\sconseil)?|investi(e?s)?$|sans invest.+)" test_str = ("NE PAS PRENDRE EN COMPTE\n" "concorde invest\n" "invest conseil\n" "pro immo invest\n" "avons investi\n" "très investies\n" "nous sommes investis\n" "sans investissement suplémentaire\n\n" "pattern = ((concorde|immo )?invest\\b(\\sconseil)?|investi(e?s)?$|sans invest.+)\n" "---------------------------------------------------------------\n" "pattern = (investi[a-z]+|invest )\n\n" "idéal invest\n" "ideal premier investissement\n" "ideal occupant et investisseur\n" "idéal pour investir\n" "projet pour investisseurs\n" "pour faire un investissement\n" "idéal pour investissement\n" "local pour investissement\n" "local commercial pour investisseur\n" "parfait pour des investisseurs\n" "idéal investisseur\n" "idéal pour utilisateur ou investisseur\n" "idéal profession libérale ou investisseur\n\n" "s’adressant à des investisseurs\n" "dédié à l'investissement\n" "vente destinée à investisseurs\n" "a vendre investissement\n" "à vendre dans le cadre d'un investissement\n\n" "des activités comme investisseur\n\n" "bel investissement\n" "excellent investissement\n\n" "opportunité investisseur\n" "opportunité d'implantation ou d'investissement\n" "opportunité pour investir\n" "opportunité à l'investissement\n\n" "exclusivité investisseur\n" "exclusivité vente a investisseur\n" "spécial investisseurs\n\n" "rentabilité pour investissement\n" "investissement à forte rentabilité\n" "produit investissement\n\n" "rentabilité 8% pour investisseurs\n" "investissement sans risque\n" "investir en toute sécurité\n\n" "investissement idéal\n\n" "soyez les premiers à investir\n\n" "disponible à la vente en investissement\n" "vente de murs occupés à investisseur\n\n" "investir sur ces murs libres\n\n" "propose à la l'investissement\n\n" "conviendrait à un investisseur\n\n") matches = re.finditer(regex, test_str, re.MULTILINE) 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