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

/
/

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"<div[^<>]*>([\s\S]*?)<\/div>").unwrap(); let string = "<?xml version=\"1.0\" encoding=\"utf-8\" standalone=\"no\"?> <!DOCTYPE html PUBLIC \"-//W3C//DTD XHTML 1.1//EN\" \"http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd\"> <html xmlns=\"http://www.w3.org/1999/xhtml\"> <head> <title>A Dança dos Dragões - As Crônicas de Gelo e Fogo</title> <link href=\"../Styles/9788580445763_a_danca_dos_dragoes.css\" rel=\"stylesheet\" type=\"text/css\" /> </head> <body id=\"x9788580445763_a_danca_dos_dragoes\" xml:lang=\"pt-PT\"> <div class=\"Basic-Text-Frame\"> <p class=\"TOC\"><span class=\"Bold\">&nbsp;</span></p> <p class=\"after-10\"><span class=\"Bold\">&nbsp;</span></p> <p class=\"titulo-ficha-tecnica-before10\" id=\"toc_marker-2\"><span class=\"Bold\">Ficha Técnica</span></p> <p class=\"texto-ficha-tecnica\"><span class=\"Regular\">Copyright © George R. R. Martin</span></p> <p class=\"texto-ficha-tecnica\"><span class=\"Regular\">Todos os direitos reservados.</span></p> <p class=\"texto-ficha-tecnica\"><span class=\"Regular\">Versão brasileira © 2012 Texto Editores Ltda.</span></p> <p class=\"texto-ficha-tecnica\"><span class=\"Regular\">Título original: A Dance with Dragons<br /> <br /></span></p> <p class=\"texto-ficha-tecnica\"><span class=\"Regular\">Diretor editorial: Pascoal Soto</span></p> <p class=\"texto-ficha-tecnica\"><span class=\"Regular\">Produtora editorial: Sonnini Ruiz</span></p> <p class=\"texto-ficha-tecnica\"><span class=\"Regular\">Assistente editorial: Carolina Pereira da Rocha<br /> <br /></span></p> <p class=\"texto-ficha-tecnica\"><span class=\"Regular\">Coordenação editorial: Estúdio Sabiá</span></p> <p class=\"texto-ficha-tecnica\"><span class=\"Regular\">Preparação de texto: Rosane Albert</span></p> <p class=\"texto-ficha-tecnica\"><span class=\"Regular\">Revisão: Leandro Morita, Valéria Sanalios, Bruno SR</span></p> <p class=\"texto-ficha-tecnica\"><span class=\"Regular\">Ilustração da capa: Marc Simonetti</span></p> <p class=\"texto-ficha-tecnica\"><span class=\"Regular\">Capa: Scintilla Lima</span></p> <p class=\"texto-ficha-tecnica\"><span class=\"Regular\"><br /> <br /> Dados Internacionais de Catalogação na Publicação (cip)</span></p> <p class=\"texto-ficha-tecnica\"><span class=\"Regular\">(Câmara Brasileira do Livro, SP, Brasil)<br /> <br /> <br /> Martin, George R. R.</span></p> <p class=\"texto-ficha-tecnica\"><span class=\"Regular\">A dança dos dragões / George R. R. Martin ;</span></p> <p class=\"texto-ficha-tecnica\"><span class=\"Regular\">tradução Marcia Blasques. − São Paulo : Leya,</span></p> <p class=\"texto-ficha-tecnica\"><span class=\"Regular\">2012. – (Coleção as crônicas de gelo e fogo ; 5)<br /> <br /> Título original: A dance with dragons.</span></p> <p class=\"texto-ficha-tecnica\"><span class=\"Regular\">ISBN 9788580445763<br /> <br /></span></p> <p class=\"texto-ficha-tecnica\"><span class=\"Regular\">1. Ficção fantástica norte-americana. I. Título. II. Série.</span></p> <p class=\"texto-ficha-tecnica\"><span class=\"Regular\">12-08553 CDD-813.5</span></p> <p class=\"texto-ficha-tecnica\"><span class=\"Regular\"><br /> <br /> Índices para catálago sistemático:</span></p> <p class=\"texto-ficha-tecnica\"><span class=\"Regular\">1. Ficção : Literatura norte-americana 813.5<br /> <br /> <br /> Texto Editores Ltda.</span></p> <p class=\"texto-ficha-tecnica\"><span class=\"Regular\">[Uma editora do grupo LeYa]</span></p> <p class=\"texto-ficha-tecnica\"><span class=\"Regular\">Rua Desembagador Paulo Passaláqua, 86</span></p> <p class=\"texto-ficha-tecnica\"><span class=\"Regular\">01248-010 – Pacaembu – São Paulo – SP</span></p> <p class=\"texto-ficha-tecnica\"><a href=\"http://www.leya.com\"><span class=\"Regular\">www.leya.com</span></a></p> </div> </body> </html> "; // result will be a tuple containing the start and end indices for the first match in the string let result = regex.captures(string); let (start, end) = match result { Some((s, e)) => (s, e), None => { // ... } }; println!("{}", &string[start, end]); }

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/