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

/
/
gmi

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*DETECTORES SELECCIONADOS HABILITADOS).{40}" test_str = (" DETECTORES SELECCIONADOS HABILITADOS EVENTO NUMERO 2423 EM 20:38 13-03-15 \n" " RELES ISOLADOS EVENTO NUMERO 2496 EM 05:21 23-03-15 \n" " EVACUAÇAO EVENTO NUMERO 2497 EM 14:49 23-03-15 \n" " ALARME SILENCIADO EVENTO NUMERO 2498 EM 14:49 23-03-15 \n" " ENTRADA DE ALTERAÇOES NIVEL ACESSO 02 EVENTO NUMERO 2499 EM 14:49 23-03-15 \n" " SAIDA SEM INTRODUÇAO DE ALTERAÇOES EVENTO NUMERO 2500 EM 14:49 23-03-15 \n" " REPOSIÇAO GERAL REPOSIÇOES 0004 EVENTO NUMERO 2501 EM 14:50 23-03-15 \n" "DEFEITO ZONA 023 DSP 094 L03 SIRENE Portaria DISPOSITIVO REMOVIDO EVENTO NUMERO 2502 EM 17:50 24-03-15 \n" "FOGO 001 ZONA 011 DSP 033 L01 OPTICO Carrocel, ADM. Setor Qualidade EVENTO NUMERO 2503 EM 03:20 25-03-15 \n" " SAIDA SEM INTRODUÇAO DE ALTERAÇOES EVENTO NUMERO 2504 EM 03:25 25-03-15 \n" " SAIDA SEM INTRODUÇAO DE ALTERAÇOES EVENTO NUMERO 2505 EM 03:26 25-03-15 \n" " EVACUAÇAO EVENTO NUMERO 2506 EM 03:26 25-03-15 \n" " RELES HABILITADOS EVENTO NUMERO 2507 EM 03:26 25-03-15 \n" " EVACUAÇAO DESLIGADA EVENTO NUMERO 2508 EM 03:26 25-03-15 \n\n") matches = re.finditer(regex, test_str, re.MULTILINE | re.IGNORECASE) 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