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"(?<!\{)\{([^\s}]+)\}(?!\})" test_str = ("<?php\n\n" "return\n" "[\n" " 'server'=> [\n" " 'host'=> 'smtp.saluddigital.net',\n" " //'helo'=> url('domain'),\n" " 'username'=> 'php7@saluddigital.net',\n" " 'password'=> 'x5~JkKU+X(NY4R$C',\n" " 'port'=> '25',\n" " 'charset'=> '{\\web.charset}',\n" " ],\n" " 'mails'=> [\n" " // Para especificar varias direcciones, separarlas por comas\n" " // Para especificar un nombre para una dirección, usamos el formato\n" " // estándard nombre <email>, <email>.\n" " // Ejemplos:\n" " // 'jatubio@saluddigital.net'\n" " // 'Andrés Pozo <apozo@saluddigital.net>, ergon@saluddigital.net'\n" " //\n" " // Usar {domain} para sustituirlo por el dominio actual\n" " 'default'=> [\n" " 'asunto'=> '{\\web.titulo}',\n" " 'from'=> '{\\web.titulo} <info@[url domain]>',\n" " 'replyto'=> '',\n" " // Poner siempre en copia\n" " 'cc'=> '',\n" " // Poner siempre en copia oculta\n" " 'cco'=> '',\n" " // Direcciones para enviar la copia de administración\n" " 'admin'=> 'jatubio@saluddigital.net',\n" " // Activar/Desactivar la copia de administración\n" " 'adminsend'=> true,\n" " // Enviar una copia si está activado el flag de debug\n" " 'debug'=> 'jatubio@saluddigital.net',\n" " // Activar/Desactivar la copia de debug\n" " 'debugsend'=> true,\n" " // Modificar alguna de las opciones anteriores si cumple el filtro\n" " 'filtros'=> [\n" " 'paises'=> [\n" " 'filtro'=> [\n" " 'Pais'=>'España',\n" " ],\n" " 'opciones'=> [\n" " 'asunto'=>'Hola desde España',\n" " ],\n" " ],\n" " ],\n" " ],\n" " // Formulario de contacto\n" " 'contacto'=> [\n" " 'asunto'=> 'Contacto desde {\\web.titulo}',\n" " 'from'=> '{\\web.titulo} <contacto@[url domain]>',\n" " // Campos a incluir en el [repetir datos]\n" " // Si está vacío, se incluyen todos\n" " 'campos'=> ['Nombre', 'Apellidos', 'Telefono', 'EMail', 'Pais', 'Curso', 'Comentario'],\n" " 'campoTo' => 'Nombre <EMail>',\n" " //template=> 'contacto',\n" " ],\n" " ],\n" " 'templates'=> [\n" " 'base'=>'General',\n" " ],\n" "];\n\n" "//--------------------------------------------------------------------\n" "//--------------------------------------------------------------------\n" "// Ejemplos\n" "//--------------------------------------------------------------------\n" "//--------------------------------------------------------------------\n" "return\n" "[\n" " 'server'=> [\n" " 'host'=> 'smtp.saluddigital.net',\n" " 'helo'=> url('domain'),\n" " 'username'=> 'php7@saluddigital.net',\n" " 'password'=> 'x5~JkKU+X(NY4R$C',\n" " 'port'=> '25',\n" " 'charset'=> '{\\web.charset}',\n" " ],\n" " // Para especificar varias direcciones, separarlas por comas\n" " // Para especificar un nombre para una dirección, usamos el formato\n" " // nombre=>email.\n" " // Ejemplos:\n" " // 'jatubio@saluddigital.net'\n" " // 'Andrés Pozo=>apozo@saluddigital.net, ergon@saluddigital.net'\n" " 'default'=> [\n" " 'asunto'=> '{\\web.titulo}',\n" " 'from'=> '{\\web.titulo}=>info@[url domain]',\n" " 'replyto'=> '',\n" " // Poner siempre en copia\n" " 'cc'=> '',\n" " // Poner siempre en copia oculta\n" " 'cco'=> '',\n" " // Direcciones para enviar la copia de administración\n" " 'admin'=> 'jatubio@saluddigital.net',\n" " // Activar/Desactivar la copia de administración\n" " 'adminsend'=> true,\n" " // Enviar una copia si está activado el flag de debug\n" " 'debug'=> 'jatubio@gmail.com',\n" " // Activar/Desactivar la copia de debug\n" " 'debugsend'=> true,\n" " // Modificar alguna de las opciones anteriores si cumple el filtro\n" " 'filtros'=> [\n" " 'paises'=> [\n" " 'filtro'=> [\n" " 'Pais'=>'España',\n" " ],\n" " 'opciones'=> [\n" " 'asunto'=>'Hola desde España',\n" " ],\n" " ],\n" " 'cursos' => [\n" " 'filtro'=> [\n" " 'Curso'=>'Consulta General',\n" " ],\n" " 'opciones'=> [\n" " 'cco'=>'consultas@gmai.com',\n" " ],\n" " ]\n" " ],\n" " ],\n" " // Formulario de contacto\n" " 'contacto'=> [\n" " 'asunto'=> 'Contacto desde {\\web.titulo}',\n" " 'from'=> '{\\web.titulo} <contacto@[url domain]>',\n" " 'filtros'=> [\n" " 'paises'=> [\n" " 'filtro'=> [\n" " 'Pais'=>'Costa Rica, Francia, Perú',\n" " ],\n" " 'opciones'=> [\n" " 'asunto'=>'Hola desde Costa Rica',\n" " 'from'=> '{\\web.titulo\n" "} <costarica@[url domain]>',\n" " ],\n" " 'activo'=> false,\n" " ],\n" " 'casos'=> [\n" " 'filtro'=> [\n" " 'NumCaso'=>'1, 8, 10',\n" " ],\n" " 'opciones'=> [\n" " '{{asunto}}'=>'Consulta sobre un caso',\n" " 'cc'=> 'especialista@gmail.com',\n" " ],\n" " ],\n" " 'cursos'=> [\n" " 'activo'=> false,\n" " ]\n" " ],\n" " ],\n" "];") 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