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

/
/

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"((\d+) (C\.F\.R|U\.S\.C). (§) ((\d+\.?\d+)(\(\w+\))?(\(\d+\))?(\(\w+\))?( \w+ )(\(\w+\))?(;)))|(\d+) (U\.S\.C)\. (§) (\d+)(\W+)(\w+)(\W+)(\d+)(\W+)(\w+)(\W+)|((\d+) (C\.F\.R|U\.S\.C). (§) (\d+.\.?\d+))" test_str = "\" 5 C.F.R. § 2424.32(a) and (c); <i>AFGE, Local 1858</i>, 56 FLRA 1115, 1117 (2001). The Authority has held that a union's lack of response constituted a concession to an<final tooltip='CUE phrase-fact'> <final tooltip='CUE phrase-fact'> <final tooltip='CUE phrase-fact'> <final tooltip='CUE phrase-fact'>agency's argument</final> the proposal interferes with its management right to layoff employees under 5 U.S.C. § 7106(a)(2)(A). SOP at 11. The Agency<intial tooltip='CUE phrase-intial'> <intial tooltip='CUE phrase-intial'> <intial tooltip='CUE phrase-intial'> <intial tooltip='CUE phrase-intial'> affects management's right to layoff employees under § 7106(a)(2)(A) of the Statute, it is outside the<rationale tooltip='CUE phrase-fact'> <rationale tooltip='CUE phrase-fact'> <rationale tooltip='CUE phrase-fact'> <rationale tooltip='CUE phrase-fact'> <rationale 5 C.F.R. § 2424.32 tooltip='CUE phrase-fact'> <rationale tooltip='CUE phrase-fact'> <rationale tooltip='CUE phrase-fact'> <rationale tooltip='CUE phrase-fact'> <rationale tooltip='CUE phrase-fact'> <rationale tooltip='CUE phrase-fact'> <rationale tooltip='CUE phrase-fact'> <rationale tooltip='CUE phrase-fact'> <rationale tooltip='CUE phrase-fact'> <rationale tooltip='CUE phrase-fact'> <rationale tooltip='CUE phrase-fact'>duty to bargain</rationale> </rationale> </rationale> </rationale> </rationale> </rationale> </rationale> </rationale> </rationale> </rationale> </rationale> </rationale> </rationale> </rationale> </rationale> . <i>Int'l Ass'n of Machinists &amp; Aerospace Workers</i>, 59 FLRA 830, 831 (2004); <i>Tidewater Va. Fed. Employees Metal Trades Council</i>, 58 FLRA 561, 563 (2003) (citing <i>NFFE, Local 1904</i>, 57 FLRA 28, 29 (2001)). In accordance with Authority precedent set forth above, Proposal 2 is outside the<rationale tooltip='CUE phrase-fact'> <rationale tooltip='CUE phrase-fact'> <rationale tooltip='CUE phrase-fact'> <rationale tooltip='CUE phrase-fact'> <rationale tooltip='CUE phrase-fact'> <rationale tooltip='CUE phrase-fact'> <rationale tooltip='CUE phrase-fact'> <rationale tooltip='CUE phrase-fact'> <rationale tooltip='CUE phrase-fact'> <rationale tooltip='CUE phrase-fact'> <rationale tooltip='CUE phrase-fact'> <rationale tooltip='CUE phrase-fact'> <rationale tooltip='CUE phrase-fact'> <rationale tooltip='CUE phrase-fact'> <rationale tooltip='CUE phrase-fact'>duty to bargain</rationale> </rationale> </rationale> </rationale> </rationale> </rationale> </rationale> </rationale> </rationale> </rationale> </rationale> </rationale> </rationale> </rationale> </rationale> . n2 <footnote fn-num=\"2\">Given the above,<rationale tooltip='CUE phrase-fact'>it is unnecessary to address the</rationale>Agency's argument that Proposal 2 concerns supervisors and therefore is only negotiable at the election of the Agency.</footnote><b>IX. Order</b> Proposal 1 is negotiable only at the election of the Agency and Proposal 2 is not<fact tooltip='CUE phrase-fact'> <fact tooltip='CUE phrase-fact'> <fact tooltip='CUE phrase-fact'> <fact tooltip='CUE phrase-fact'> <fact tooltip='CUE phrase-fact'> <fact tooltip='CUE phrase-fact'> <fact tooltip='CUE phrase-fact'> <fact tooltip='CUE phrase-fact'> <fact tooltip='CUE phrase-fact'> <fact tooltip='CUE phrase-fact'>within the<rationale tooltip='CUE phrase-fact'> <rationale tooltip='CUE phrase-fact'> <rationale tooltip='CUE phrase-fact'> <rationale tooltip='CUE phrase-fact'> <rationale tooltip='CUE phrase-fact'> <rationale tooltip='CUE phrase-fact'> <rationale tooltip='CUE phrase-fact'> <rationale tooltip='CUE phrase-fact'> <rationale tooltip='CUE phrase-fact'> <rationale tooltip='CUE phrase-fact'> <rationale tooltip='CUE phrase-fact'> <rationale tooltip='CUE phrase-fact'> <rationale tooltip='CUE phrase-fact'> <rationale tooltip='CUE phrase-fact'> <rationale tooltip='CUE phrase-fact'>duty to bargain</rationale> </rationale> </rationale> </rationale> </rationale> </rationale> </rationale> </rationale> </rationale> </rationale> </rationale> </rationale> </rationale> </rationale> </rationale> </fact> </fact> </fact> </fact> </fact> </fact> </fact> </fact> </fact> </fact> , therefore, the petition with respect to Proposal 2<final tooltip='CUE phrase-fact'>is dismissed</final> . </content><br>" matches = re.search(regex, test_str) if matches: print ("Match was found at {start}-{end}: {match}".format(start = matches.start(), end = matches.end(), match = matches.group())) for groupNum in range(0, len(matches.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = matches.start(groupNum), end = matches.end(groupNum), group = matches.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