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

/
/
gx

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""" (?(DEFINE) (?<recurs> (?! {@|@} ) [^|] [^{@|\\]* ( \\.[^{@|\\]* )* | (?R) ) ) {@ (?<If>\w+)- (?<Condition>(%?\w++ (:\w+)*)* ) (?<True> [|] [^{@|]*+ (?&recurs)* ) (?<False> [|] (?&recurs)* )? \s*@} """ 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 = re.finditer(regex, test_str, re.VERBOSE) 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