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""" (?(DEFINE) (?<recurs> (?! {@|@} ) [^|] [^{@|\\]* ( \\.[^{@|\\]* )* | (?R) ) ) {@ (?<If>\w+)- (?<Condition>(%?\w++ (:\w+)*)* ) (?<True> [|] [^{@|]*+ (?&recurs)* ) (?<False> [|] (?&recurs)* )? \s*@} """, flags=re.VERBOSE) test_str = ("{@if-statement:sub%statement2|\n" "<header id=\"header_home\">\n" " <div class=\"in\">\n" " <div class=\"top\">\n" " <h1 class=\"logo\"><a href=\"/\"><img src=\"/img/logo-home.png\" alt=\"\"></a></h1>\n" " <div class=\"login_outer_wrapper\">\n" " <button id=\"login\"><div class=\"a\"><i class=\"stripe\"><i></i></i>Log in</div></button>\n" " <div id=\"login_wrapper\">\n" " <form method=\"post\" action=\"{^login^}\" id=\"form_login_global\">\n" " <div class=\"form_field no_description\">\n" " <label>{!auth:login_email!}</label>\n" " <div class=\"input\"><input type=\"text\" name=\"form[login]\"></div>\n" " </div>\n" " <div class=\"form_field no_description password\">\n" " <label>{!auth:password!}</label>\n" " <div class=\"input\"><input type=\"password\" name=\"form[password]\"></div>\n" " </div>\n" " <div class=\"remember\">\n" " <input type=\"checkbox\" name=\"remember\" id=\"remember_me_check\" checked>\n" " <label for=\"remember_me_check\"><i class=\"fa fa-check\" aria-hidden=\"true\"></i>Remember</label>\n" " </div>\n" " <div class=\"submit_box\">\n" " <button class=\"btn btn_check\">Log in</button>\n" " </div>\n" " </form>\n" " </div>\n" " </div>\n" " </div>\n" " <div class=\"content clr\">\n" " <div class=\"main_menu\">\n" " <a href=\"\">\n" " <i class=\"ico a\"><i class=\"fa fa-lightbulb-o\" aria-hidden=\"true\"></i></i>\n" " <span>Idea</span>\n" " <div>&nbsp;</div>\n" " </a>\n" " <a href=\"\">\n" " <i class=\"ico b\"><i class=\"fa fa-user\" aria-hidden=\"true\"></i></i>\n" " <span>FFa</span>\n" " </a>\n" " <a href=\"\">\n" " <i class=\"ico c\"><i class=\"fa fa-briefcase\" aria-hidden=\"true\"></i></i>\n" " <span>Buss</span>\n" " </a>\n" " </div>\n" " <div class=\"text_wrapper\">\n\n" " <div>\n" " <div class=\"register_wrapper\">\n" " <a id=\"main_register\" class=\"btn register\">Załóż konto</a>\n" " <form method=\"post\" action=\"{^login^}\" id=\"form_register_home\">\n" " <div class=\"form_field no_description\">\n" " <label>{!auth:email!}</label>\n" " <div class=\"input\"><input type=\"text\" name=\"form2[email]\"></div>\n" " </div>\n" " <div class=\"form_field no_description password\">\n" " <label>{!auth:password!}</label>\n" " <div class=\"input tooltip\"><input type=\"password\" name=\"form2[password]\"><i class=\"fa fa-info-circle tooltip_open\" aria-hidden=\"true\" title=\"{!auth:password_format!}\"></i></div>\n\n" " </div>\n" " <div class=\"form_field terms no_description\">\n" " <div class=\"input\">\n" " <input type=\"checkbox\" name=\"form2[terms]\" id=\"terms_check\">\n" " <label for=\"terms_check\"><i class=\"fa fa-check\" aria-hidden=\"true\"></i>Agree</label>\n" " </div>\n" " </div>\n" " <div class=\"form_field no_description\">\n" " <div cl\\|\\|ass=\"input captcha_wrapper\">\n" " <div class=\"g-recaptcha\" data-sitekey=\"{%captcha_public_key%}\"></div>\n" " </div>\n" " </div>\n" " <div class=\"submit_box\">\n" " <button class=\"btn btn_check\">{!auth:register_btn!}</button>\n" " </div>\n" " </form>\n" " </div>\n" " </div>\n" " </div>\n" " </div>\n" " </div>\n" "</header>|{@if-statement2|echo this|{@if-statement2|echo this|echo othe\\|\\|rwise@}@}\n" "@}") 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