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

r"
"
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><strong>PRESIDENTE ANDRÉS MANUEL LÓPEZ OBRADOR:<\/strong>\r?\n((?:(?!<p><strong>)^[^\r\n]+\r?\n)+)" test_str = ("<p><strong>ROGELIO JIMÉNEZ PONS:</strong> Quisiera\n" "<p>Text here...</p>\n" "<p><strong>PRESIDENTE ANDRÉS MANUEL LÓPEZ OBRADOR:</strong>\n" "<p>Text here...</p>\n" "<p>Text here...</p>\n" "<p><strong>PREGUNTA:</strong>\n" "<p>Text here...</p>\n" "<p><strong>PRESIDENTE ANDRÉS MANUEL LÓPEZ OBRADOR:</strong>\n" "<p>Y la información específica la vamos a difundir a través de una página en internet, que es: www.participacionsocial.gob.mx, en su momento vamos a establecer ahí la metodología que se va a utilizar para determinar la ubicación de los módulos,\n" " el número de boletas, la forma de identificación de las personas participantes y esa metodología va a explicar los criterios como la población, el padrón, la accesibilidad y la viabilidad de todo esto.</p>\n" " <p>También vamos a poner toda la información del proyecto para que cualquier persona pueda consultarla y de esta manera ir fortaleciendo también toda la cuestión de la transparencia y rendición de cuentas que hemos llevado a cabo en todos los\n" " procesos de consulta y ejercicios participativos durante este año de gobierno.</p>\n" " <p>Gracias.</p>\n" " <p>Ahora, vamos a escuchar a Adelfo Regino con el tema de las consultas indígenas.</p>\n" "<p><strong>INTERLOCUTOR:</strong>\n" "<p>Text here...</p>\n" "<p>Text here...</p>\n" "<p><strong>PRESIDENTE ANDRÉS MANUEL LÓPEZ OBRADOR:</strong>\n" "<p>Text here...</p>\n" "<p>Text here...</p>\n" "<p>Text here...</p>\n" "<p>Text here...</p>\n" "<p>Text here...</p>\n" "<p><strong>INTERLOCUTOR:</strong>\n") 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