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

/
/
gU

Test String

Substitution

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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#"(?U)<a(.*)href="([^"]*)"(.*)>"#).unwrap(); let string = "<p><b>Piano:</b><br /></p><p><a class=\"dialog function_link\" dclass=\"function_dialog\" dwidth=\"500\" dheight=\"auto\" href=\"http://www.smeg.it/ajax/view_function/3374\"><img src=\"http://www.smeg.it/smeg_it/images/functions/0/0/Func2302.jpg\" alt=\"Griglie in ghisa\" title=\"Griglie in ghisa\" /></a> <a class=\"dialog function_link\" dclass=\"function_dialog\" dwidth=\"500\" dheight=\"auto\" href=\"http://www.smeg.it/ajax/view_function/3368\"><img src=\"http://www.smeg.it/smeg_it/images/functions/0/0/Func2300.jpg\" alt=\"Bruciatore Ultrarapido\" title=\"Bruciatore Ultrarapido\" /></a> <br /></p><p class=\"dot\">7 bruciatori a gas, di cui 1 Ultrarapido (4,2 kW)<br /></p><p><br /></p><p><b>Forno principale, superiore:</b><br /></p><p><a class=\"dialog function_link\" dclass=\"function_dialog\" dwidth=\"500\" dheight=\"auto\" href=\"http://www.smeg.it/ajax/view_function/3372\"><img src=\"http://www.smeg.it/smeg_it/images/functions/0/0/A.jpg\" alt=\"A\" title=\"A\" /></a> <a class=\"dialog function_link\" dclass=\"function_dialog\" dwidth=\"500\" dheight=\"auto\" href=\"http://www.smeg.it/ajax/view_function/4225\"><img src=\"http://www.smeg.it/smeg_it/images/functions/0/0/Func1548.jpg\" alt=\"4 livelli di cottura\" title=\"4 livelli di cottura\" /></a> <a class=\"dialog function_link\" dclass=\"function_dialog\" dwidth=\"500\" dheight=\"auto\" href=\"http://www.smeg.it/ajax/view_function/3369\"><img src=\"http://www.smeg.it/smeg_it/images/functions/0/0/Func2320.jpg\" alt=\"Smalto Ever Clean\" title=\"Smalto Ever Clean\" /></a> <a class=\"dialog function_link\" dclass=\"function_dialog\" dwidth=\"500\" dheight=\"auto\" href=\"http://www.smeg.it/ajax/view_function/3665\"><img src=\"http://www.smeg.it/smeg_it/images/functions/0/0/Func1518.jpg\" alt=\"Volta Mobile\" title=\"Volta Mobile\" /></a> <a class=\"dialog function_link\" dclass=\"function_dialog\" dwidth=\"500\" dheight=\"auto\" href=\"http://www.smeg.it/ajax/view_function/3371\"><img src=\"http://www.smeg.it/smeg_it/images/functions/0/0/Func2318.jpg\" alt=\"Interno porta tuttovetro\" title=\"Interno porta tuttovetro\" /></a> <a class=\"dialog function_link\" dclass=\"function_dialog\" dwidth=\"500\" dheight=\"auto\" href=\"http://www.smeg.it/ajax/view_function/3671\"><img src=\"http://www.smeg.it/smeg_it/images/functions/0/0/Func2316.jpg\" alt=\"Vetro interno rimovibile\" title=\"Vetro interno rimovibile\" /></a> <a class=\"dialog function_link\" dclass=\"function_dialog\" dwidth=\"500\" dheight=\"auto\" href=\"http://www.smeg.it/ajax/view_function/3373\"><img src=\"http://www.smeg.it/smeg_it/images/functions/0/0/Func2314.jpg\" alt=\"Porta a triplo vetro\" title=\"Porta a triplo vetro\" /></a> <a class=\"dialog function_link\" dclass=\"function_dialog\" dwidth=\"500\" dheight=\"auto\" href=\"http://www.smeg.it/ajax/view_function/3370\"><img src=\"http://www.smeg.it/smeg_it/images/functions/0/0/Func2324.jpg\" alt=\"Raffreddamento tangenziale\" title=\"Raffreddamento tangenziale\" /></a> <a class=\"dialog function_link\" dclass=\"function_dialog\" dwidth=\"500\" dheight=\"auto\" href=\"http://www.smeg.it/ajax/view_function/3675\"><img src=\"http://www.smeg.it/smeg_it/images/functions/0/0/Func2328.jpg\" alt=\"Guide telescopiche\" title=\"Guide telescopiche\" /></a> <br /></p><p class=\"dot\">Forno elettrico multifunzione termoventilato, 7 funzioni<br /></p><p>compresa funzione di pulizia Vapor Clean<br /></p><p class=\"dot\">Opzione programmazione di inizio e fine cottura con allarme<br /></p><p>acustico di fine cottura<br /></p><p class=\"dot\">Display / Orologio: elettronico a 5 tasti<br /></p><p><b>Forno secondario, inferiore:</b><br /></p><p><a class=\"dialog function_link\" dclass=\"function_dialog\" dwidth=\"500\" dheight=\"auto\" href=\"http://www.smeg.it/ajax/view_function/3372\"><img src=\"http://www.smeg.it/smeg_it/images/functions/0/0/A.jpg\" alt=\"A\" title=\"A\" /></a> <a class=\"dialog function_link\" dclass=\"function_dialog\" dwidth=\"500\" dheight=\"auto\" href=\"http://www.smeg.it/ajax/view_function/4225\"><img src=\"http://www.smeg.it/smeg_it/images/functions/0/0/Func1548.jpg\" alt=\"4 livelli di cottura\" title=\"4 livelli di cottura\" /></a> <a class=\"dialog function_link\" dclass=\"function_dialog\" dwidth=\"500\" dheight=\"auto\" href=\"http://www.smeg.it/ajax/view_function/3369\"><img src=\"http://www.smeg.it/smeg_it/images/functions/0/0/Func2320.jpg\" alt=\"Smalto Ever Clean\" title=\"Smalto Ever Clean\" /></a> <a class=\"dialog function_link\" dclass=\"function_dialog\" dwidth=\"500\" dheight=\"auto\" href=\"http://www.smeg.it/ajax/view_function/3665\"><img src=\"http://www.smeg.it/smeg_it/images/functions/0/0/Func1518.jpg\" alt=\"Volta Mobile\" title=\"Volta Mobile\" /></a> <a class=\"dialog function_link\" dclass=\"function_dialog\" dwidth=\"500\" dheight=\"auto\" href=\"http://www.smeg.it/ajax/view_function/3371\"><img src=\"http://www.smeg.it/smeg_it/images/functions/0/0/Func2318.jpg\" alt=\"Interno porta tuttovetro\" title=\"Interno porta tuttovetro\" /></a> <a class=\"dialog function_link\" dclass=\"function_dialog\" dwidth=\"500\" dheight=\"auto\" href=\"http://www.smeg.it/ajax/view_function/3671\"><img src=\"http://www.smeg.it/smeg_it/images/functions/0/0/Func2316.jpg\" alt=\"Vetro interno rimovibile\" title=\"Vetro interno rimovibile\" /></a> <a class=\"dialog function_link\" dclass=\"function_dialog\" dwidth=\"500\" dheight=\"auto\" href=\"http://www.smeg.it/ajax/view_function/3373\"><img src=\"http://www.smeg.it/smeg_it/images/functions/0/0/Func2314.jpg\" alt=\"Porta a triplo vetro\" title=\"Porta a triplo vetro\" /></a> <a class=\"dialog function_link\" dclass=\"function_dialog\" dwidth=\"500\" dheight=\"auto\" href=\"http://www.smeg.it/ajax/view_function/3370\"><img src=\"http://www.smeg.it/smeg_it/images/functions/0/0/Func2324.jpg\" alt=\"Raffreddamento tangenziale\" title=\"Raffreddamento tangenziale\" /></a> <a class=\"dialog function_link\" dclass=\"function_dialog\" dwidth=\"500\" dheight=\"auto\" href=\"http://www.smeg.it/ajax/view_function/3675\"><img src=\"http://www.smeg.it/smeg_it/images/functions/0/0/Func2328.jpg\" alt=\"Guide telescopiche\" title=\"Guide telescopiche\" /></a> <br /></p><p class=\"dot\">Forno elettrico multifunzione ventilato, 7 funzioni<br /></p><p>compresa funzione di pulizia Vapor Clean<br /></p><p><b>Forno ausiliario, superiore:</b><br /></p><p><a class=\"dialog function_link\" dclass=\"function_dialog\" dwidth=\"500\" dheight=\"auto\" href=\"http://www.smeg.it/ajax/view_function/4710\"><img src=\"http://www.smeg.it/smeg_it/images/functions/0/0/Func1552.jpg\" alt=\"2 livelli di cottura\" title=\"2 livelli di cottura\" /></a> <a class=\"dialog function_link\" dclass=\"function_dialog\" dwidth=\"500\" dheight=\"auto\" href=\"http://www.smeg.it/ajax/view_function/3369\"><img src=\"http://www.smeg.it/smeg_it/images/functions/0/0/Func2320.jpg\" alt=\"Smalto Ever Clean\" title=\"Smalto Ever Clean\" /></a> <a class=\"dialog function_link\" dclass=\"function_dialog\" dwidth=\"500\" dheight=\"auto\" href=\"http://www.smeg.it/ajax/view_function/3665\"><img src=\"http://www.smeg.it/smeg_it/images/functions/0/0/Func1518.jpg\" alt=\"Volta Mobile\" title=\"Volta Mobile\" /></a> <a class=\"dialog function_link\" dclass=\"function_dialog\" dwidth=\"500\" dheight=\"auto\" href=\"http://www.smeg.it/ajax/view_function/3371\"><img src=\"http://www.smeg.it/smeg_it/images/functions/0/0/Func2318.jpg\" alt=\"Interno porta tuttovetro\" title=\"Interno porta tuttovetro\" /></a> <a class=\"dialog function_link\" dclass=\"function_dialog\" dwidth=\"500\" dheight=\"auto\" href=\"http://www.smeg.it/ajax/view_function/3671\"><img src=\"http://www.smeg.it/smeg_it/images/functions/0/0/Func2316.jpg\" alt=\"Vetro interno rimovibile\" title=\"Vetro interno rimovibile\" /></a> <a class=\"dialog function_link\" dclass=\"function_dialog\" dwidth=\"500\" dheight=\"auto\" href=\"http://www.smeg.it/ajax/view_function/3373\"><img src=\"http://www.smeg.it/smeg_it/images/functions/0/0/Func2314.jpg\" alt=\"Porta a triplo vetro\" title=\"Porta a triplo vetro\" /></a> <a class=\"dialog function_link\" dclass=\"function_dialog\" dwidth=\"500\" dheight=\"auto\" href=\"http://www.smeg.it/ajax/view_function/3370\"><img src=\"http://www.smeg.it/smeg_it/images/functions/0/0/Func2324.jpg\" alt=\"Raffreddamento tangenziale\" title=\"Raffreddamento tangenziale\" /></a> <br /></p><p class=\"dot\">Forno elettrico 1 funzione<br /></p><p><br /></p><p class=\"dot\">Vano portaoggetti con apertura a cassetto<br /></p><p class=\"dot\"><b>Porta dei forni principale e secondario con apertura <br /></p><p>laterale</b><br /></p><p class=\"dot\">DIMENSIONI: LxPxH 110x60x91 cm</p>"; let substitution = "<a$1href=\"javascript:alert(\\'Test\\');\"$3>"; // 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/