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

Generated Code

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r"(sous[- ]sol)" test_str = ("sous-sol de xm²\n" "surface en sous-sol de d'une superfice de xx m²\n" "sous-sol d'une superficie de xx m²\n" "surface au sous-sol de xx m²\n" "surface en sous-sol d'environ xx m²\n" "sous-sol: xxm²\n" "xx m² : - un sous-sol\n" "sous-sol xx m²\n" "surface sous-sol accessible de xx m²\n" "en sous-sol de xx m\n" "xx m² de sous sol\n" "xx m² situé au sous-sol\n" "en sous-sol 42 m2\n" "au sous-sol, une surface de 25 m²\n" "xx m² de surface commerciale en sous-sol\n" "surface commerciale en sous-sol de xx m²\n" "xxm de sous-sol \n" "sous-sol sur cour\n" "sous-sol de plain pied de xxm\n" "sous-sol propose une surface de xx m\n" "sous-sol et terrasse de xx m²\n" "sous-sol de plus xx m2\n" "sous-sol entièrement carrelé de xx m²\n" "sous sol accessible par escalier de xx m2\n" "sous sol sain de xxm2\n" "sous-sol avec zone de stockage de xx m²\n" "sous-sol idéal pour stockage de xxm²\n" "sous sol pour le stockage de xx m2\n" "sous-sol avec extraction de xxm2\n" "sous-sol à rénover de xx m2\n" "sous sol de xxm2\n" "sous-sol d'une cuisine de xx m2\n" "sous-sol avec réserve et vestiaire de xx m²\n" "sous-sol à usage de réserve de xx m²\n" "sous-sol une cave de xxm²") 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