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

/
/
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"( ?ibid\., *(([0-3]?[0-9]\.)?[01]?[0-9]\.[0-9]{2,4}), *([^;]{0,50}) *(;|\) ?\.))" test_str = " en août, ni sur ceux récoltés ensuite (16.10.2014, M. Garnier-Delcourt & J. Thorn), peut-être parce que les sporophores étaient un peu dégradés par les intempéries ? Cortinarius emollitoides Bidaud, MoënneLocc. & Reumaux (Fig. 2) = C. galeobdolon Melot sensu auct. ; C. causticus Fr. sensu. auct. non Brandrud et al. (1998) Ard. : Consthum, Fridbësch (71/113), plantation d’Abies et de Picea, 12.11.2012, Ch. Reckinger 319 (h) ; ibid., 23.9.2014, Ch. Reckinger 405 (h) ; ibid., 23.9.2014, Ch. Reckinger 406 (h) ; ibid., 23.9.2014, Ch. Reckinger 406 (h) ; ibid., 23.9.2014, Ch. Reckinger 406 (h) ; ibid., 23.9.2014, Ch. Reckinger 406 (h) ; ibid., 23.9.2014, Ch. Reckinger 406 (h) ; ibid., 23.9.2014, Ch. Reckinger 406 (h) ; ibid., 23.9.2014, Ch. Reckinger 406 (h). Dans le sous-genre Myxacium (Fr.) Trog, qui regroupe en principe des cortinaires à chapeau et pied visqueux, la section Vibratiles Melot se distingue par l’amertume de la cuticule et généralement aussi de tout le sporophore. Elle comprend des espèces assez colorées (en jaune-brun ou rougebrun) ou peu co" 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