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

/
/

Test String

Code Generator

Language

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#"(?><(?:(?:(?:(script|style|object|embed|applet|noframes|noscript|noembed)(?:\s+(?>"[\S\s]*?"|'[\S\s]*?'|(?:(?!\/>)[^>])?)+)?\s*>)[\S\s]*?<\/\1\s*(?=>))|(?:\/?(?!body)[\w:]+\s*\/?)|(?:(?!body)[\w:]+\s+(?:"[\S\s]*?"|'[\S\s]*?'|[^>]?)+\s*\/?)|\?[\S\s]*?\?|(?:!(?:(?:DOCTYPE[\S\s]*?)|(?:\[CDATA\[[\S\s]*?\]\])|(?:--[\S\s]*?--)|(?:ATTLIST[\S\s]*?)|(?:ENTITY[\S\s]*?)|(?:ELEMENT[\S\s]*?))))>|[\S\s])*?<body(?:\s+(?>"[\S\s]*?"|'[\S\s]*?'|(?:(?!\/>)[^>])?)+)?\s*>((?:<(?:(?:(?:(script|style|object|embed|applet|noframes|noscript|noembed)(?:\s+(?>"[\S\s]*?"|'[\S\s]*?'|(?:(?!\/>)[^>])?)+)?\s*>)[\S\s]*?<\/\3\s*(?=>))|(?:\/?(?!body)[\w:]+\s*\/?)|(?:(?!body)[\w:]+\s+(?:"[\S\s]*?"|'[\S\s]*?'|[^>]?)+\s*\/?)|\?[\S\s]*?\?|(?:!(?:(?:DOCTYPE[\S\s]*?)|(?:\[CDATA\[[\S\s]*?\]\])|(?:--[\S\s]*?--)|(?:ATTLIST[\S\s]*?)|(?:ENTITY[\S\s]*?)|(?:ELEMENT[\S\s]*?))))>|[\S\s])*)<\/body\s*>"#).unwrap(); let string = "<html> <head> <meta http-equiv=\"content-type\" content=\"text/html; charset=utf-8\"> </head> <!-- <body class=\"blah\">original mock body </body> --> <body text=\"#000000\" bgcolor=\"#FFFFFF\"> <!CDATA[Raw unparsed character data can contain </body> with no problems!]]> <!-- Comments can also contain </body> --> So can JScript <script>/*<![CDATA[*/window.jQuery && jQuery.ready();/*]]>*/</script><script>if(window.mw){ mw.loader.state({\"ext.glo</body>balCssJs.site\":\"ready\",\"ext.globalCssJs.user\":\"ready\",\"site\":\"loading\",\"user\":\"ready\",\"user.groups\":\"ready\"}); }</script> <p>dpioaushd iuashdiu ashd</p> <p> has</p> <p>ud ashuod sh</p> <p>odu sad ha</p> <p>suod sh</p> <p>od uashod uahd<br> </p> <div class=\"moz-signature\">-- <br> <img src=\"cid:part1.8C289150.C3F89C42@wssim.com.br\" border=\"0\"></div> </body> </html>"; // result will be a tuple containing the start and end indices for the first match in the string let result = regex.captures(string); let (start, end) = match result { Some((s, e)) => (s, e), None => { // ... } }; println!("{}", &string[start, end]); }

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/