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"^[\s+-]?[^\s]+\s([^\s\n]+).*$" test_str = (" +883620946918182db5a277fc5e328fee3030ef79 src/dobot_cr_driver (8836209)\n" "-8fc5c05835a246d7cb46952f748efec11fbf0075 src/onrobot_driver\n" " b5704131f0e2964e4d051d5e6f6560917c2a1969 src/ros_camera\n" " 1ffdd69181389b14b7d6342f0c5bad3b45c5e32f src/ur_meta (1.1.5-315-g1ffdd69)\n" " ec2beb65afd6be5373d1e21a86dd42a07e25b447 src/ur_official_driver (v2.0.0-4-gec2beb6)\n" " 883620946918182db5a277fc5e328fee3030ef79 src/dobot_cr_driver (8836209)\n" " 8fc5c05835a246d7cb46952f748efec11fbf0075 src/onrobot_driver (8fc5c05)\n" " b5704131f0e2964e4d051d5e6f6560917c2a1969 src/ros_camera (heads/develop)\n" " 1ffdd69181389b14b7d6342f0c5bad3b45c5e32f src/ur_meta (1.1.5-315-g1ffdd69)\n" " ec2beb65afd6be5373d1e21a86dd42a07e25b447 src/ur_official_driver (v2.0.0-4-gec2beb6)") 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