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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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)calypso:calypsoObject.{10,150}xsi:type="calypso:(\w{2,50})"#).unwrap(); let string = "<calypso:calypsoDocument xmlns:datauploader=\"http://www.calypso.com/datauploader\" xmlns:ftp=\"http://www.calypso.com/ftp\" xmlns:liquidityrule=\"http://www.calypso.com/liquidityrule\" xmlns:bloomberg=\"http://www.calypso.com/bloomberg\" xmlns:liquiditycriteria=\"http://www.calypso.com/liquiditycriteria\" xmlns:pricingscript=\"http://www.calypso.com/pricingscript\" xmlns:am=\"http://www.calypso.com/am\" xmlns:liquidityposition=\"http://www.calypso.com/liquidityposition\" xmlns:scriptableOTC=\"http://www.calypso.com/scriptableOTC\" xmlns:pricingsheet=\"http://www.calypso.com/pricingsheet\" xmlns:matching=\"http://www.calypso.com/matching\" xmlns:scheduler=\"http://www.calypso.com/scheduler\" xmlns:ns20=\"http://www.calypso.com/HedgeAccounting\" xmlns:liquidityreporting=\"http://www.calypso.com/liquidityreporting\" xmlns:taskstation=\"http://www.calypso.com/taskstation\" xmlns:kpiservice=\"http://www.calypso.com/kpiservice\" xmlns:liquiditycore=\"http://www.calypso.com/liquiditycore\" xmlns:calypso=\"http://www.calypso.com/xml\" xmlns:assumption=\"http://www.calypso.com/assumption\" xmlns:liquidityclassification=\"http://www.calypso.com/liquidityclassification\" xmlns:collateral=\"http://www.calypso.com/collateral\" xmlns:calculationserver=\"http://www.calypso.com/calculationserver\" xmlns:bondexoticnote=\"http://www.calypso.com/bondexoticnote\"><calypso:calypsoObject xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" xsi:type=\"calypso:FutureCommodity\" version=\"14-0\" action=\"SAVE\"><calypso:identification><calypso:versionedIdentifier version=\"0\" code=\"21866845\" codifier=\"CPSLIVE\"/></calypso:identification><calypso:definition><calypso:contract><calypso:type>com.calypso.tk.product.FutureContract</calypso:type><calypso:separator>#</calypso:separator><calypso:identifier code=\"USD#LME#LMEZinc\" codifier=\"convention\"/><calypso:calypsoBusinessKey><calypso:propertyName>currency</calypso:propertyName><calypso:propertyValue>USD</calypso:propertyValue></calypso:calypsoBusinessKey><calypso:calypsoBusinessKey><calypso:propertyName>exchange</calypso:propertyName><calypso:propertyValue>LME</calypso:propertyValue></calypso:calypsoBusinessKey><calypso:calypsoBusinessKey><calypso:propertyName>name</calypso:propertyName><calypso:propertyValue>LMEZinc</calypso:propertyValue></calypso:calypsoBusinessKey></calypso:contract><calypso:expirationDate>2023-10-30Z</calypso:expirationDate><calypso:firstDeliveryDate>2023-10-30Z</calypso:firstDeliveryDate><calypso:firstNotificationDate>2023-10-30Z</calypso:firstNotificationDate><calypso:lastDeliveryDate>2023-10-30Z</calypso:lastDeliveryDate><calypso:lastNotificationDate>2023-10-30Z</calypso:lastNotificationDate><calypso:tradingEndDate>2023-10-30Z</calypso:tradingEndDate><calypso:tradingStartDate>2023-10-30Z</calypso:tradingStartDate><calypso:ccpDate>2023-10-30Z</calypso:ccpDate></calypso:definition></calypso:calypsoObject></calypso:calypsoDocument>"; // 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/