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

/
/
g

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"CR.DITO\s*TUSD\s*KW\s*\-\s*APCEI\s*\-\s*N\s*CONS[A-Z.]*\s*\d{2}\/\d{4}\s*(?<VlrDNUtilCred>[0-9.-]+\,?\d*)" test_str = ("Junho 2019\n" " \n" "0606 DEBITO TUSD KW - APCEI 04/2019 65,16 0,00 0 0,00 0,00 0,00 0,00\n" "0606 DEB. DA TUSD KW-APCEI- N CONS. 04/2019 1,73 0,00 0 0,00 0,00 0,00 0,00\n" "0606 CREDITO DA TUSD KW - APCEI 06/2019 -22.034,82 0,00 0 0,00 0,00 0,00 0,00\n" "0606 CREDITO TUSD KW-APCEI -N CONS. 06/2019 -238,64 0,00 0 0,00 0,00 0,00 0,00\n" " \n" "Janeiro 2020\n" " \n" "0606 DEBITO TUSD KW - APCEI 11/2019 50,85 0,00 0 0,00 0,00 0,00 0,00\n" "0606 DEB. DA TUSD KW-APCEI- N CONS. 11/2019 0,92 0,00 0 0,00 0,00 0,00 0,00\n" "0606 CREDITO DA TUSD KW - APCEI 01/2020 -22.514,07 0,00 0 0,00 0,00 0,00 0,00\n" "0606 CREDITO TUSD KW-APCEI -N CONS. 01/2020 -404,71 0,00 0 0,00 0,00 0,00 0,00\n" " \n" "Abril 2020\n" " \n" "0606 DÉBITO TUSD KW-APCEI 02/2020 102,86 0,00 0 0,00 0,00 0,00 0,00\n" "0606 DÉBITO TUSD KW-APCEI - N CONSUMIDA 02/2020 0,92 0,00 0 0,00 0,00 0,00 0,00\n" "0606 CREDITO TUSD KW-APCEI 04/2020 -23.968,26 0,00 0 0,00 0,00 0,00 0,00\n" "0606 CREDITO TUSD KW-APCEI - N CONSUMIDA 02/2020 -0,92 0,00 0 0,00 0,00 0,00 0,00\n" "0601 Substituição Tributária - Crédito 378.862,670 0,248265 94.058,22 94.058,22 32 30.098,63 0,00 0,00 0,00\n" "0906 Substituição Tributária - Débito 378.862,670 0,248265 -63.959,60 0,00 0 0,00 0,00 0,00 0,00") matches = re.finditer(regex, test_str) 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