Regular Expressions 101

Save & Share

  • Regex Version: ver. 3
  • Update Regex
    ctrl+⇧+s
  • Save new Regex
    ctrl+s
  • Add to Community Library

Flavor

  • PCRE2 (PHP >=7.3)
  • PCRE (PHP <7.3)
  • ECMAScript (JavaScript)
  • Python
  • Golang
  • Java 8
  • .NET 7.0 (C#)
  • Rust
  • Regex Flavor Guide

Function

  • Match
  • Substitution
  • List
  • Unit Tests

Tools

Sponsors
There are currently no sponsors. Become a sponsor today!
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

/
/
gx

Test String

Code Generator

Generated Code

// include the latest version of the regex crate in your Cargo.toml extern crate regex; use regex::Regex; fn main() { let regex = Regex::new(r"(?x)(?(DEFINE) (?<recurs> (?! {@|@} ) [^|] [^{@|\\]* ( \\.[^{@|\\]* )* | (?R) ) ) {@ (?<If>\w+)- (?<Condition>(%?\w++ (:\w+)*)* ) (?<True> [|] [^{@|]*+ (?&recurs)* ) (?<False> [|] (?&recurs)* )? \s*@}").unwrap(); let string = "{@if-statement:sub%statement2| <header id=\"header_home\"> <div class=\"in\"> <div class=\"top\"> <h1 class=\"logo\"><a href=\"/\"><img src=\"/img/logo-home.png\" alt=\"\"></a></h1> <div class=\"login_outer_wrapper\"> <button id=\"login\"><div class=\"a\"><i class=\"stripe\"><i></i></i>Log in</div></button> <div id=\"login_wrapper\"> <form method=\"post\" action=\"{^login^}\" id=\"form_login_global\"> <div class=\"form_field no_description\"> <label>{!auth:login_email!}</label> <div class=\"input\"><input type=\"text\" name=\"form[login]\"></div> </div> <div class=\"form_field no_description password\"> <label>{!auth:password!}</label> <div class=\"input\"><input type=\"password\" name=\"form[password]\"></div> </div> <div class=\"remember\"> <input type=\"checkbox\" name=\"remember\" id=\"remember_me_check\" checked> <label for=\"remember_me_check\"><i class=\"fa fa-check\" aria-hidden=\"true\"></i>Remember</label> </div> <div class=\"submit_box\"> <button class=\"btn btn_check\">Log in</button> </div> </form> </div> </div> </div> <div class=\"content clr\"> <div class=\"main_menu\"> <a href=\"\"> <i class=\"ico a\"><i class=\"fa fa-lightbulb-o\" aria-hidden=\"true\"></i></i> <span>Idea</span> <div>&nbsp;</div> </a> <a href=\"\"> <i class=\"ico b\"><i class=\"fa fa-user\" aria-hidden=\"true\"></i></i> <span>FFa</span> </a> <a href=\"\"> <i class=\"ico c\"><i class=\"fa fa-briefcase\" aria-hidden=\"true\"></i></i> <span>Buss</span> </a> </div> <div class=\"text_wrapper\"> <div> <div class=\"register_wrapper\"> <a id=\"main_register\" class=\"btn register\">Załóż konto</a> <form method=\"post\" action=\"{^login^}\" id=\"form_register_home\"> <div class=\"form_field no_description\"> <label>{!auth:email!}</label> <div class=\"input\"><input type=\"text\" name=\"form2[email]\"></div> </div> <div class=\"form_field no_description password\"> <label>{!auth:password!}</label> <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> </div> <div class=\"form_field terms no_description\"> <div class=\"input\"> <input type=\"checkbox\" name=\"form2[terms]\" id=\"terms_check\"> <label for=\"terms_check\"><i class=\"fa fa-check\" aria-hidden=\"true\"></i>Agree</label> </div> </div> <div class=\"form_field no_description\"> <div cl\\|\\|ass=\"input captcha_wrapper\"> <div class=\"g-recaptcha\" data-sitekey=\"{%captcha_public_key%}\"></div> </div> </div> <div class=\"submit_box\"> <button class=\"btn btn_check\">{!auth:register_btn!}</button> </div> </form> </div> </div> </div> </div> </div> </header>|{@if-statement2|echo this|{@if-statement2|echo this|echo othe\\|\\|rwise@}@} @}"; // result will be an iterator over tuples containing the start and end indices for each match in the string let result = regex.captures_iter(string); for mat in result { println!("{:?}", mat); } }

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 Rust, please visit: https://docs.rs/regex/latest/regex/