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"(seuil|d[ée]tecteurs?|variateur|dalles?|seuil)(lumineux?|lumineuses?|luminosit[ée])" test_str = ("locaux lumineux\n" "locaux traversants et lumineux\n" "locaux rénovés sont lumineux\n" "local commercial de 47 m² très lumineux\n\n" "bureaux lumineux\n" "bureaux très lumineux\n" "bureaux haussmaniens ultra-lumineux\n" "bureaux cloisonnés et lumineux\n" "bureaux neufs et lumineux\n" "bureau privatif cosy et lumineux \n" "bureaux agréables et lumineux\n\n" "openspace lumineux\n" "espaces de travail sont lumineux\n" "plateaux très lumineux\n" "plateaux sont très lumineux\n" "duplex atypique et lumineux\n" "bien agencé et lumineux\n\n" "surface lumineuse\n" "boutique très lumineuse\n\n" "locaux en état d'usage belle luminosité\n" "bénéficie d’une luminosité\n" "offrants une grande luminosité\n" "en angle et d’une belle luminosité\n" "verrière apportant élégance et luminosité\n" "belle luminosité\n" "grande luminosité\n" "bonne luminosité\n" "hauteur sous plafond lumineux\n\n" "[NE PAS TENIR COMPTE]\n" "seuil de luminosité\n" "détecteurs présence et luminosité\n" "variateur en fonction de la luminosité\n" "points lumineux\n" "pavés lumineux\n" "zone d'activité lumineuse\n" "dalle quartz belle luminosité\n" "dalles lumineuses\n" "plafond en dalle minérale points lumineux\n" "cage d'escalier très lumineuse") 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