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#"<div id="pageContent">[\s\S]*<div id="pageContent">"#).unwrap(); let string = " \"HTML Tidy for Mac OS X (vers 31 October 2006 - Apple Inc. build 15.15), see www.w3.org\"> <title>02.00: Page 1</title> <meta charset=\"utf-8\"> <script type=\"text/javascript\"> var pg_csslibs = []; // CSS Libs for this Page var pg_jslibs = []; // JS Libs for this Page </script> <script src=\"../../global/js/settings.js\" id=\"settingJS\" type= \"text/javascript\"> </script> </head> <body> <div id=\"pageContent\"> <!-- CONTENT GOES HERE --> <div id=\"pageContent\"> <div> <p><a href=\"pop/02_00_01/02_00_01_pop01.htm\" class= \"modal-pop\"><strong>Print</strong></a> the Carousel of Progress Checklist provided below to keep track of your progress through the <span class=\"lang\" data-term= \"module_name\">module</span>. It is important that you read each page and complete all practice activities in every <span class=\"lang\" data-term=\"lesson_name"; // 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/