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#"<a href="http.?:.*(youtube.com|.*be\/|.*embed\/|watch?. v=|(\w{11})).?<\/a>"#).unwrap(); let string = "the following URL will be found in a &lt;A&gt;:<br> <em> <a href=\"https://www.youtube.com/watch?t=61&amp;v=JozAmXo2bDE\" rel=\"nofollow\">https://www.youtube.com/watch?t=61&amp;v=JozAmXo2bDE</a> <br> <a href=\"https://soundcloud.com/buzzdeny/sets/deutsch-er-hiphop-rap\" rel=\"nofollow\">https://soundcloud.com/buzzdeny/sets/deutsch-er-hiphop-rap</a> <a href=\"https://www.youtube.com/watch?v=VH2QAMMSL40\" rel=\"nofollow\">https://www.youtube.com/watch?v=VH2QAMMSL40</a> <br> <a href=\"http://www.youtube.com/embed/NLqAF9hrVbY\" rel=\"nofollow\">http://www.youtube.com/embed/NLqAF9hrVbY</a> <br> <a href=\"http://youtu.be/NLqAF9hrVbY\" rel=\"nofollow\">http://youtu.be/NLqAF9hrVbY</a> </em> <br> <a href=\"http://www.youtube.com/sandalsResorts#p/c/54B8C800269D7C1B/0/FJUvudQsKCM\" rel=\"nofollow\">http://www.youtube.com/sandalsResorts#p/c/54B8C800269D7C1B/0/FJUvudQsKCM</a> </p> <a href=\"/uploads/files/1438381231924-humanistische-friedenspartei.mp3\">Humanistische - Friedenspartei.mp3</a> <p>nice... <a href=\"/uploads/files/1438418374790-drumloop053_ambnt_160_x_sc5.wav\">DRUMLOOP053_AMBNT_160_X_SC5.wav</a></p> <a href=\"/uploads/files/1438418374790-drumloop053_ambnt_160_x_sc5.wav\">DRUMLOOP053_AMBNT_160_X_SC5.wav</a> <p>infos:<br> <a href=\"https://github.com/ogerly/nodebb-plugin-youtube-lite/blob/master/library.js\" rel=\"nofollow\">https://github.com/ogerly/nodebb-plugin-youtube-lite/blob/master/library.js</a> </p> <p><a href=\"https://github.com/ogerly/nodebb-plugin-youtube-lite\" rel=\"nofollow\">https://github.com/ogerly/nodebb-plugin-youtube-lite</a></p> </div>"; // 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/