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

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"(?m)(?<=<!-- Template Nav Start -->[\n])([\n\s\S]*?)(?=[\s\n]*?<!-- Template Nav End -->)").unwrap(); let string = "<!DOCTYPE html> <html lang=\"en\"> <head> <meta charset=\"UTF-8\"> <meta http-equiv=\"X-UA-Compatible\" content=\"IE=edge\"> <meta name=\"viewport\" content=\"width=device-width, initial-scale=1.0\"> <meta property=\"og:site_name\" content=\"WD Proposal\"> <meta property=\"og:title\" content=\"Your new outdoor living space.\"> <meta property=\"og:image\" content=\"https://www.WhitmerDecks.com/Proposal/eProposal/img/wdLogoName.png\"> <meta property=\"og:description\" content=\"Here you can view the proposal from Whitmer Decks, LLC\"> </meta> <!-- General scripts & styles --> <link rel=\"stylesheet\" href=\"css/styles.css\"> <link rel=\"stylesheet\" href=\"css/cwBootstrap.css\"> <script src=\"js/cwBootstrap.js\" defer></script> <!-- Google Fonts --> <link href=\"https://fonts.googleapis.com/css?family=Roboto:300,400,500,700&display=swap\" rel=\"stylesheet\"> <!-- Page title and end of general head --> <title>WD Proposal</title> <!-- Page specific scripts and styles --> <script src=\"js/about.js\" defer></script> </head> <body> <!-- Template Nav Start --> <nav> <ul> <li><a href=\"index.html\">Home</a></li> <li><a href=\"about.html\">About</a></li> <li>Item X</li> <li>Item Y</li> </ul> </nav> <!-- Template Nav End --> <p> The about page </p> </body> </html>"; // 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/