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#"(?<AttributeName>(?:src|background))\s*=\s*["'](?<AttributeValue>(?:[^"'])*)"#).unwrap(); let string = "<html> <table id='tblTest' border=\"1\"> <tr> <td colspan=\"1\" >CellA</td> </tr> <tr> <td>Click<a href=\"http://mail.google.com\" >here</a></td> </tr> <tr> <td> <img src=\"http://wcrustine.org/Portals/0/click_here_button.jpg\" style=\"width:100px;height:100px;\"></img></td> </tr> <tr> <td background=\"https://ci6.googleuser.com/proxy/d-NpaBfbly5hKSic8pomfvI4scwJqkF2wwmRqEB4stR8jfO7jo-Sx-JcVLfIXqw5gJnd05Rl0aY3evT2DhmS6he85ifLGQA=s0-d-e1-ft#http://newsletter.mydomain.com/template/header_bg.jpg\" bgcolor=\"#336699\" height=\"100\" style=\"background:url(https://ci5.googleuser.com/proxy/d-NpaBfbly5hKSic8pomfvI4scwJqkF2wwmRqEB4stR8jJrvfO7jo-Sx-JcVLfIgJnd05Rl0aY3evT2DhmS6LU85ifLGQA=s0-d-e1-ft#http://newsletter.mydomain.com/template/header_bg.jpg) top left repeat #336699\" width=\"\"> &nbsp; </td> </tr> </table> </html>"; // 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/