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"(?<=\,)\d{2}").unwrap(); let string = "http://regexr.com     Welcome to RegExr v2.1 by gskinner.com, proudly hosted by Media Temple! Edit the Expression & Text to see matches. Roll over – matches – or the expression for details. Undo mistakes with cmd-z. Save  Favorites & Share $33 expressions with «friends or the Community. Explore your results with Tools. A full Reference & Help is available $2 in the Library, or watch the video Tutorial. année 201, années 1969 à 1974, – anné 2015, mois 2013   Voici un -deuxième- paragraphe, avec – ÉT “retour” « régulier ». Une clause clause inefficace suivi d’une autre clause. La suite du texte se — poursuit toujours — normalement. Voici un autre paragraphe avec un retour forcé (shift return). Nous verrons comment les GREP saisiront cette donnée. Les GREPs sont intégrés dans ces 2 applications — InDesign et Dreamweaver! InDesign,InDesign 2.0, “InDesign CS” and InDesign CS2 The quick brown fox jumps up and down. abc abc abc abc BONJOUR SOLEIL.    Tot, tot, Toto, toto, totoo, totoooo, tatoo, tato, teratatotinotto •          $22.999, 23,99$, 19.99 $ $2.99, 22,99$, 2,99$, 2,99 $ 2.53%, 20% 1.89L, 1,89 L — 2 pour 1$ 514-123-4567  •  h4N 1X7 • h8t •                      h4N1X72                      Ajout code postal •          h8T mot à trouver Charles ixv 1/3, 234/56   12h22, 12:00, 12am, 12 pm, 11h30 am, 8 PM, 6H15, 08:00, 6.00 pm année 2017, années 1970 à 1974, anné 2016, mois 2014 22/11/2016, 01-08-2017, 01|02|2015, 20.12.2014, 2/3/2012   Sample text for testing: SAMPLE abcdefghijklmnopqrstuvwxyz ABCDEFGHIJKLMNOPQRSTUVWXYZ 0123456789 _+-.,!@#$%^&*();\\/|<>”’ 12345 -98.7 3.141 .6180 9,000 +42 1234 - 5678, 1234  -  1234 3oF, -10oC   555.123.4567   +1-(800)-555-2468 (123)-(456)-(7890) (xxx (xxx) xxxxx (xx) xxx) foo@demo.net   bar.ba@test.co.uk good4you@yummy.com somebody@somewhere.ca, another.somebody@coucouland.com www.demo.com   http://foo.co.uk/ http://regexr.com/foo.html?q=bar https://mediatemple.netx   76 g ou/or 85 g  22,99 ch./ ea. 22.99 222,22 2,222 22,222 22, ,11, 22,22$ 22,22 $ 195 ml, 273 ml ou/or 198 g 1 $ "; // 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/