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

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)id\=\"(?<id>[a-zA-Z][^_]+(\.*))"#).unwrap(); let string = "10-10-2019 14:04:25.863 +0200 WARN DispatchSjaak - Queued job id=\"c1111__c63422sss23344__search__search12339_157e345.73734_AF27BCF9-C4E0-4D04-B4E3-3r\", seadex=application_wab_p id=\"w34_aW0uY3Jpc2lz_aW0uY3Jpc2lz__search__search36_15703344710104.14022286_FB3D64CC-984D-4FAB-B724-5D14BA490FE3AppID == \"ANDROID\", \"MB Android App\", search_id=\"1570701613.3403_5F230059-1DF0-4750-B165-087Der444425949E17\" - QUEUED reason=\"The maximum nu = \"HELL\", \"MB\", search_id=\"xxx1570701613.3403_5F230059-1DF0-4750-B165-087Der444425933244349E17\" - QUEUED reason=\"The maximum nu"; // 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/