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"_P(?:N(?:X?1|Q[OSV]|)|P(?:GE|H1|(?:[HI]O|IS|X)[12]|HS2|Y))\s\w+_V[A-Z0-9]*\b(*SKIP)(*F)|\w+_V[A-Z0-9]*\b" test_str = "Ya_UH and_CC then_RT uhm_NN1 we_PPIS2 wrote_VVD in_RP but_CCB already_RR taken_VVN up_RP that_DD1 day_NNT1 that_CST we_PPIS2 wanted_VVD actually_RR they_PPHS2 said_VVD still_RR available_JJ you_PPY know_VV0 so_RR by_II that_DD1 time_NNT1 we_PPIS2 we_PPIS2 write_VV0 in_II our_APPGE letter_NN1 two_MC weeks_NNT2 later_RRR already_RR taken_VVN up_RP Quite_RG good_RR uh_UH P ICE-SIN:S1A-001#74:1:B Ask_VV0 her_PPHO1 I_PPIS1 left_VVD my_APPGE house_NN1 at_II one_MC1 met_VVD PRO_NN1 in_II school_NN1 at_II two_MC Ya_PPY so_RR waited_VVD you_PPY know_VV0 they_PPHS2 say_VV0 half_DB hour_NNT1 later_RRR And_CC and_CC it_PPH1 was_VBDZ still_RR drizzling_JJ and_CC raining_VVG" 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