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

// 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#"href="([^"]+)""#).unwrap(); let string = " <!DOCTYPE html> <html lang=\"fr\"> <head></head> <body> <div id=\"wm-ipp\" class=\"\" lang=\"en\" style=\"display: block;\"></div> <!-- BEGIN WAYBACK TOOLBAR INSERT --> <script src=\"/static/js/disclaim-element.js\" type=\"text/javascript\"></script> <script src=\"/static/js/graph-calc.js\" type=\"text/javascript\"></script> <script src=\"/static/jflot/jquery.min.js\" type=\"text/javascript\"></script> <script type=\"text/javascript\"></script> <style type=\"text/css\"></style> <script type=\"text/javascript\"></script> <!-- END WAYBACK TOOLBAR INSERT --> <header id=\"main_header\"> <div class=\"header_content\"></div> </header> <div id=\"main_content\"> <div id=\"under_top_event\"></div> <div id=\"breadcrumbs\"></div> <div id=\"main_search\"></div> <div id=\"content\"> <div id=\"page_test\" class=\"home\"> <div id=\"topline\"> <h1> TESTS </h1> </div> <div class=\"large_column left_column\"> <a class=\"top\" title=\"Lire le test : The Final Fantasy\" href=\"/web/20121023121603/http://www.gameweb.fr/articles/test-65-the-final-fantasy-3ds-page-opinion.html\"></a> <div class=\"separation\" style=\"margin: 20px 0;\"></div> <a class=\"high\" title=\"Lire le test : El Shaddai : Ascension of The Metatron\" href=\"/web/20121023121603/http://www.gameweb.fr/articles/test-63-el-shaddai-ascension-of-the-metatron-ps3-page-opinion.html\"></a> <a class=\"high\" title=\"Lire le test : Heroes of Ruin\" href=\"/web/20121023121603/http://www.gameweb.fr/articles/test-62-heroes-of-ruin-3ds-page-opinion.html\"></a> <a class=\"high\" title=\"Lire le test : Prototype 2\" href=\"/web/20121023121603/http://www.gameweb.fr/articles/test-61-prototype-2-ps3-page-opinion.html\"></a> <a class=\"high\" title=\"Lire le test : Rayman Origins\" href=\"/web/20121023121603/http://www.gameweb.fr/articles/test-60-rayman-origins-ps3-page-opinion.html\"></a> </div> <div class=\"medium_column right_column\" style=\"padding-top: 70px;\"> <a class=\"medium\" title=\"Lire le test : Mass Effect 3\" href=\"/web/20121023121603/http://www.gameweb.fr/articles/test-59-mass-effect-3-x360-page-opinion.html\"> <span class=\"small title\"></span> <span class=\"put_score score\"></span> <span class=\"description\"></span> </a> <div class=\"separation\" style=\"margin: 10px 0;\"></div> <a class=\"medium\" title=\"Lire le test : Pandora's Tower\" href=\"/web/20121023121603/http://www.gameweb.fr/articles/test-58-pandoras-tower-wii-page-opinion.html\"> <span class=\"small title\"></span> <span class=\"put_score score\"></span> <span class=\"description\"></span> </a> <div class=\"separation\" style=\"margin: 10px 0;\"></div> <a class=\"medium\" title=\"Lire le test : I am alive\" href=\"/web/20121023121603/http://www.gameweb.fr/articles/test-57-i-am-alive-x360-page-opinion.html\"></a> <div class=\"separation\" style=\"margin: 10px 0;\"></div> <a class=\"medium\" title=\"Lire le test : Silent hill downpour\" href=\"/web/20121023121603/http://www.gameweb.fr/articles/test-56-silent-hill-downpour-ps3-page-opinion.html\"></a> <div class=\"separation\" style=\"margin: 10px 0;\"></div> <a class=\"medium\" title=\"Lire le test : Naruto Storm Generations\" href=\"/web/20121023121603/http://www.gameweb.fr/articles/test-55-naruto-storm-generations-x360-page-opinion.html\"></a> <div class=\"separation\" style=\"margin: 10px 0;\"></div> <a class=\"medium\" title=\"Lire le test : Street Fighter x Tekken\" href=\"/web/20121023121603/http://www.gameweb.fr/articles/test-54-street-fighter-x-tekken-ps3-page-opinion.html\"></a> <div class=\"separation\" style=\"margin: 10px 0;\"></div> <a class=\"medium\" title=\"Lire le test : Ninja Gaiden 3\" href=\"/web/20121023121603/http://www.gameweb.fr/articles/test-53-ninja-gaiden-3-ps3-page-opinion.html\"></a> <div class=\"separation\" style=\"margin: 10px 0;\"></div> <a class=\"medium\" title=\"Lire le test : Asura's Wrath\" href=\"/web/20121023121603/http://www.gameweb.fr/articles/test-52-asuras-wrath-ps3-page-opinion.html\"></a> <div class=\"separation\" style=\"margin: 10px 0;\"></div> <a class=\"medium\" title=\"Lire le test : The Last Story\" href=\"/web/20121023121603/http://www.gameweb.fr/articles/test-51-the-last-story-wii-page-opinion.html\"></a> <div class=\"separation\" style=\"margin: 10px 0;\"></div> <a class=\"medium\" title=\"Lire le test : Xenoblade\" href=\"/web/20121023121603/http://www.gameweb.fr/articles/test-50-xenoblade-wii-page-opinion.html\"></a> <div class=\"separation\" style=\"margin: 10px 0;\"></div> <a class=\"medium\" title=\"Lire le test : SSX\" href=\"/web/20121023121603/http://www.gameweb.fr/articles/test-48-ssx-ps3-page-opinion.html\"></a> <div class=\"separation\" style=\"margin: 10px 0;\"></div> <a class=\"medium\" title=\"Lire le test : Syndicate\" href=\"/web/20121023121603/http://www.gameweb.fr/articles/test-47-syndicate-pc-page-opinion.html\"></a> <div class=\"separation\" style=\"margin: 10px 0;\"></div> <a class=\"medium\" title=\"Lire le test : Resident Evil Revelations\" href=\"/web/20121023121603/http://www.gameweb.fr/articles/test-46-resident-evil-revelations-3ds-page-opinion.html\"></a> <div class=\"separation\" style=\"margin: 10px 0;\"></div> <a class=\"medium\" title=\"Lire le test : Binary Domain\" href=\"/web/20121023121603/http://www.gameweb.fr/articles/test-45-binary-domain-ps3-page-opinion.html\"></a> <div class=\"separation\" style=\"margin: 10px 0;\"></div> <a class=\"medium\" title=\"Lire le test : Catherine\" href=\"/web/20121023121603/http://www.gameweb.fr/articles/test-43-catherine-x360-page-opinion.html\"></a> <div class=\"separation\" style=\"margin: 10px 0;\"></div> <a class=\"medium\" title=\"Lire le test : Soulcalibur V\" href=\"/web/20121023121603/http://www.gameweb.fr/articles/test-44-soulcalibur-v-ps3-page-opinion.html\"></a> <div class=\"separation\" style=\"margin: 10px 0;\"></div> </div> </div> </div> </div> <footer id=\"main_footer\"></footer> </body> </html> <!-- FILE ARCHIVED ON 12:16:03 oct. 23, 2012 AND … --> "; // 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/