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

/
/
gm

Test String

Substitution

Processing...

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"(?m)^.*?\((.*)\).*$").unwrap(); let string = " claudiu.cismaru (Claudiu Cismaru) SPEAKER radu.mihailas (Radu Mihăilă) SPEAKER alex_macau (Alex Macau) SPEAKER angela.milas (Angela Palcu) SPEAKER andrada.rupacici (Andrada Rupacici) SPEAKER gary_star (Gabi Gidei) SPEAKER mihai.moje (Mihai Moje) ADMIN paul.ciocmareanu (Paul Adrian Ciocmareanu) SPEAKER ionut.marghidanu (Ionut Marghidanu) SPEAKER eduard.hirsch (Eduard Hirsch) SPEAKER simonabelintan (Simona Bitu) SPEAKER ade.scutca (Adela Scutca) SPEAKER roibu-florin (Florin Roibu) SPEAKER live:oanamariavlad (Oana Poenar (Vlad)) SPEAKER live:andrei.trancota (Andrei Trancota) SPEAKER live:ozy24us (Emanuel Craciun) SPEAKER adrian.mosneagu23 (Adrian Mosneagu) SPEAKER daniela.busu (Daniela Busu) SPEAKER live:florin.turdasan (Florin Turdasan) SPEAKER live:daniel.boita_1 (Daniel Boita) SPEAKER denis.buliga (Denis Buliga) SPEAKER live:jean.goujon_1 (Jean-Baptiste Goujon) SPEAKER jurjandrei90 (Andrei Jurj) SPEAKER i_pasca (Ioan Pasca) SPEAKER claudiu0386 (Claudiu Mardarasevici) SPEAKER didi.popoviciu (Didi Popoviciu) SPEAKER anda.lele (Alexandra Lele) SPEAKER lorand.varga (Lorand Varga) SPEAKER live:412602f6b1e34602 (Mihaela Lemeni) SPEAKER lvudesign (Liviu Iancu) SPEAKER octavia_stancu (Ava Stancu) SPEAKER live:422c271cb4bb230c (Beatrice Blidariu) SPEAKER live:raresistoc1_1 (Rares Istoc) SPEAKER live:octavia_octi30 (Octavia Bradea) SPEAKER live:paula.dragoman (Paula Dragoman) SPEAKER live:sanda.popoiu (Sanda Popoiu) ADMIN live:aciu.alexandru (Alexandru Aciu) ADMIN live:sirbu.sorin.cristian (Sorin Sirbu) SPEAKER live:ana.tutuianu_1 (Ana Tutuianu) SPEAKER narcis.oancea (narcis oancea) ADMIN live:raresturc (Turc Rares) ADMIN live:8922ae5e5ee0572e (Eduard Daniel Cocirla) SPEAKER adelabalans (Adela Balan) ADMIN tudor.vioreanu (Tudor Vioreanu) ADMIN live:madalin.crestescu (Madalin Crestescu) SPEAKER live:bokorb (Bokor Béla) SPEAKER live:lavinia.a.stoia (Lavinia Stoia) ADMIN timoce.ana (Ana Tutuianu) SPEAKER live:ded6104985160d9b (Mircea Grigoras) SPEAKER iancic.bogdan (Bogdan Iancic) SPEAKER"; let substitution = "$1"; // result will be a String with the substituted value let result = regex.replace_all(string, substitution); println!("{}", result); }

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/