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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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

/
/
gmx

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#"(?mx)(?(DEFINE) (?<void>br|img|area|base|col|command|embed|hr|input|keygen|link|meta|param|source|track|wbr|!DOCTYPE) (?<any>[^<>]*+) ) <div \s class="card"> (?P<pair> (?&any) (:? <(?P<v_tag>(?!\/)(?&void))(?&any)> (?:(?&pair) | (?&any))*+ (<\/(?P=v_tag)>)? | <(?P<tag>(?!\/)[^<> ]++)(?&any)> (?:(?&pair) | (?&any))*+ <\/(?P=tag)> ) (?&any) )* <\/div>"#).unwrap(); let string = "<!DOCTYPE html> <html> <head> <title>Example</title> </head> <body> <div class=\"card-container\"> <div class=\"card\"> <h5>First MD Card</h5> <img src=\"https://mdbootstrap.com/img/Photos/Horizontal/Nature/4-col/img%20(34).jpg\" alt=\"Card image cap\"> <p> Lorem ipsum dolor sit amet consectetur adipisicing elit. Sapiente fugiat accusamus excepturi rem temporibus nobis natus. </p> </div> <div class=\"slider\"> <ul class=\"progress-bar\"> <li class=\"active\"></li> <li></li> <li></li> </ul> </div> </div> </body> </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/