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

/
/
mg

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"((\d|:)+)\s(.+)" test_str = ("0:08 Waltz No. 2 (Dmitri Shostakovitch)\n" "4:01 Dance of the Knights (Sergei Prokofiev)\n" "9:42 Sabre Dance (Aram Khachaturian)\n" "12:09 1812 Overture Finale (Pyotr Ilyich Tchaikovsky) (My Absolute Favorite One)\n" "15:57 Flight of the Bumblebee \"From The Tale of Tsar Sultan\" (Nikolai Rimsky-Korsakov)\n" "19:31 Rite of Spring Sacrifical Dance (Igor Stravinsky)\n" "24:09 Piano Concerto No. 2 (Moderato) (Sergei Rachmaninoff)\n" "34:22 Polovtsian Dances \"From Prince Igor\" (Alexander Borodin)\n" "39:20 Etude Op. 8 No. 12 (Alexander Scriabin)\n" "41:51 Sailors' Dance (Reinhold Gliere)\n" "45:13 Dance of the Sugar Plum Fairy (Pyotr Ilylich Tchaikovsky)\n" "47:46 Piano Concerto No. 1 (Allegro) (Pyotr Ilylich Tchaikovsky)\n" "51:54 Ruslan and Lyudmila Overture (Mikhail Glinka)\n" "54:51 Swan Lake Waltz (Pyotr Ilyich Tchaikovsky)\n" "1:01:47 Dance of the Pagan Monster (Sergei Prokofiev)\n" "1:05:01 Overture from the Children of Captain Grant (Isaak Dunaevsky)\n" "1:08:52 Symphony No. 5 (Allegro Non Troppo) (Dmitri Shostakovitch) (My Favorite One)\n" "1:12:00 Swan Theme (Pyotr Ilyich Tchaikovsky)\n" "1:14:53 Night on Bald Mountain (Modest Mussorgsky)") 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