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

/
/
gm

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#"(?m)<link rel="canonical" href="(.*?)">"#).unwrap(); let string = "const regex = /\"sku\": \"(.*?)\"/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('\"sku\": \"(.*?)\"', 'gm') const str = ``<!DOCTYPE html> <!-- saved from url=(0044)https://www.daz3d.com/karmen-9-hd-pro-bundle --> <html xmlns=\"http://www.w3.org/1999/xhtml\" xml:lang=\"en\" lang=\"en\" class=\"\"><head><meta http-equiv=\"Content-Type\" content=\"text/html; charset=UTF-8\"> <title>Karmen 9 HD Pro Bundle | Daz 3D</title> <meta name=\"viewport\" content=\"width=device-width, initial-scale=1\"> <meta name=\"description\" content=\"&lt;p&gt;Introducing the Karmen 9 HD Pro Bundle. This all-inclusive bundle features a vibrant makeup look, expressions, a curly and braided bun hairstyle, apocalyptic-inspired outfits, Elemental Mage and Shadow Realm attire, and even monstrous poses to immerse \"> <meta name=\"keywords\" content=\"Karmen 9 HD Pro Bundle\"> <meta http-equiv=\"X-UA-Compatible\" content=\"IE=edge\"> <meta name=\"robots\" content=\"INDEX,FOLLOW,noai, noimageai\"> <link rel=\"icon\" href=\"https://www.daz3d.com/static/images/favicon.ico\" type=\"image/x-icon\"> <link rel=\"shortcut icon\" href=\"https://www.daz3d.com/static/images/favicon.ico\" type=\"image/x-icon\"> <!--[if lt IE 7]> <script type=\"text/javascript\"> //<![CDATA[ var BLANK_URL = '/js/blank.html'; var BLANK_IMG = '/js/spacer.gif'; //]]> </script> <![endif]--> <link rel=\"stylesheet\" href=\"./Karmen 9 HD Pro Bundle _ Daz 3D_files/design-533ce80c63b6085aedc802b14d1faa79.css\" about=\"0\"> <link rel=\"stylesheet\" href=\"./Karmen 9 HD Pro Bundle _ Daz 3D_files/product_zoom-5de5dd875434871413473d85f684dcfc.css\" about=\"1\"> <style> @keyframes spinner { 0% { transform: translateY(-50%) rotate(0deg); } 100% { transform: translateY(-50%) rotate(360deg); } } .spinner::after { animation: 1.5s linear infinite spinner; animation-play-state: inherit; border: solid 3px #cfd0d1; border-bottom-color: #1c87c9; border-radius: 50%; content: \"\"; height: 20px; width: 20px; display: inline-flex; flex-direction: column; padding-bottom: 5px; } </style> <script src=\"./Karmen 9 HD Pro Bundle _ Daz 3D_files/getIds\" type=\"text/javascript\" async=\"\"></script><script type=\"text/javascript\" id=\"www-widgetapi-script\" src=\"./Karmen 9 HD Pro Bundle _ Daz 3D_files/www-widgetapi.js.download\" async=\"\"></script><script async=\"\" src=\"./Karmen 9 HD Pro Bundle _ Daz 3D_files/fbevents.js.download\"></script><script type=\"text/javascript\" async=\"\" src=\"./Karmen 9 HD Pro Bundle _ Daz 3D_files/bat.js.download\"></script><script type=\"text/javascript\" async=\"\" src=\"./Karmen 9 HD Pro Bundle _ Daz 3D_files/pixel.js.download\"></script><script type=\"text/javascript\" async=\"\" src=\"./Karmen 9 HD Pro Bundle _ Daz 3D_files/analytics.js.download\"></script><script type=\"text/javascript\" async=\"\" src=\"./Karmen 9 HD Pro Bundle _ Daz 3D_files/js\"></script><script type=\"text/javascript\" async=\"\" src=\"./Karmen 9 HD Pro Bundle _ Daz 3D_files/destination\"></script><script src=\"./Karmen 9 HD Pro Bundle _ Daz 3D_files/tag.js.download\" type=\"text/javascript\" async=\"\" id=\"cjapitag\"></script><script async=\"\" src=\"./Karmen 9 HD Pro Bundle _ Daz 3D_files/affirm.js.download\"></script><script type=\"text/javascript\" async=\"\" src=\"./Karmen 9 HD Pro Bundle _ Daz 3D_files/0\"></script><script src=\"./Karmen 9 HD Pro Bundle _ Daz 3D_files/core-ed1ca31447e4f2e9bbf6d9ef38afe3c6.js.download\"></script> <style> @keyframes spinner { 0% { transform: translateY(-50%) rotate(0deg); } 100% { transform: translateY(-50%) rotate(360deg); } } .spinner::after { animation: 1.5s linear infinite spinner; animation-play-state: inherit; border: solid 3px #cfd0d1; border-bottom-color: #1c87c9; border-radius: 50%; content: \"\"; height: 20px; width: 20px; display: inline-flex; flex-direction: column; padding-bottom: 5px; } </style> <script src=\"./Karmen 9 HD Pro Bundle _ Daz 3D_files/zoom-fee76dde1f2c855960b29036b231c115.js.download\"></script> <script type=\"application/ld+json\">{ \"brand\": { \"name\": \"Daz 3D\", \"@type\": \"Brand\" }, \"@context\": \"https://schema.org/\", \"description\": \"Introducing the Karmen 9 HD Pro Bundle. This all-inclusive bundle features a vibrant makeup look, expressions, a curly and braided bun hairstyle, apocalyptic-inspired outfits, Elemental Mage and Shadow Realm attire, and even monstrous poses to immerse your character into any narrative from modern desert to fantasy to horror.\", \"image\": \"https://gcdn.daz3d.com/p/91909/i/shimuzu_Karmen_Pro_Bundle.jpg\", \"name\": \"Karmen 9 HD Pro Bundle\", \"offers\": { \"availability\": \"https://schema.org/InStock\", \"itemCondition\": \"https://schema.org/NewCondition\", \"price\": 185.99, \"priceCurrency\": \"USD\", \"@type\": \"Offer\" }, \"sku\": \"91909\", \"@type\": \"Product\" }</script> <link rel=\"canonical\" href=\"https://www.daz3d.com/karmen-9-hd-pro-bundle\"> <script> if (!daz) { var daz = {}; }; daz.api = new DazApi() from 331.2deg, var(--border-color-1), var(--border-color-2), var(--border-color-1), var(--border-color-2), var(--border-color-1) ) 1; } 93% { border-image: conic-gradient( from 334.8deg, var(--border-color-1), var(--border-color-2), var(--border-color-1), var(--border-color-2), var(--border-color-1) ) 1; } 94% { border-image: conic-gradient( from 338.4deg, var(--border-color-1), var(--border-color-2), var(--border-color-1), var(--border-color-2), var(--border-color-1) ) 1; } 95% { border-image: conic-gradient( from 342deg, var(--border-color-1), var(--border-color-2), var(--border-color-1), var(--border-color-2), var(--border-color-1) ) 1; } 96% { border-image: conic-gradient( from 345.6deg, var(--border-color-1), var(--border-color-2), var(--border-color-1), var(--border-color-2), var(--border-color-1) ) 1; } 97% { border-image: conic-gradient( from 349.2deg, var(--border-color-1), var(--border-color-2), var(--border-color-1), var(--border-color-2), var(--border-color-1) ) 1; } 98% { border-image: conic-gradient( from 352.8deg, var(--border-color-1), var(--border-color-2), var(--border-color-1), var(--border-color-2), var(--border-color-1) ) 1; } 99% { border-image: conic-gradient( from 356.4deg, var(--border-color-1), var(--border-color-2), var(--border-color-1), var(--border-color-2), var(--border-color-1) ) 1; } 100% { border-image: conic-gradient( from 360deg, var(--border-color-1), var(--border-color-2), var(--border-color-1), var(--border-color-2), var(--border-color-1) ) 1; } } } /* END rotate bonus box border */ /* BEGIN falling stars animation */ .bg-stars { width: 100%; height: 100%; position: absolute; top: 0; left: 0; overflow: hidden; } .bg-stars .bg-star { font-size: 1em; position: absolute; top: -25px; color: yellow; user-select: none; cursor: default; text-shadow: 0 0 1px #000; animation-name: fallingStars; animation-duration: 5s; animation-timing-function: linear; animation-iteration-count: infinite; animation-play-state: running; z-index: -1; } .bg-stars .bg-star:nth-of-type(1) { left: 10%; -webkit-animation-delay: 1s, 1s; animation-delay: 1s, 1s; } .bg-stars .bg-star:nth-of-type(2) { left: 20%; </div></body></html>(`; let m; while ((m = regex.exec(str)) !== null) { // This is necessary to avoid infinite loops with zero-width matches if (m.index === regex.lastIndex) { regex.lastIndex++; } // The result can be accessed through the `m`-variable. m.forEach((match, groupIndex) => { console.log(`Found match, group ${groupIndex}: ${match}`); }); } "; // 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/