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
Processing...

Test String

Code Generator

Language

Generated Code

import re regex = re.compile(r"\b\w*_P\w*\h+\w*_V\w*(*SKIP)(*F)|\b\w*_V\w*", flags=re.MULTILINE) 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 = regex.finditer(test_str) for match_num, match in enumerate(matches, start=1): print(f"Match {match_num} was found at {match.start()}-{match.end()}: {match.group()}") for group_num, group in enumerate(match.groups(), start=1): print(f"Group {group_num} found at {match.start(group_num)}-{match.end(group_num)}: {group}")

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