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

/
/
igm

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"(?im)<tagname((.|\n)(?!string))*?<\/tagname>").unwrap(); let string = "<?xml version=\"1.0\" encoding=\"utf-8\"?> <OdfBody Source=\"IDS\" DocumentCode=\"EQ0000000\" Serial=\"869\" Time=\"104139151\" CompetitionCode=\"PG2016\" Date=\"2016-09-02\" FeedFlag=\"P\" LogicalDate=\"2016-09-02\" DocumentType=\"DT_PARTIC\" Version=\"3\" > <Competition Code=\"PG2016\"> <Participant Parent=\"1057257\" MainFunctionId=\"AA01\" OlympicSolidarity=\"N\" Organisation=\"AUT\" Code=\"1057257\" BirthDate=\"1977-12-15\" Nationality=\"AUT\" Status=\"ACTIVE\" TVName=\"Michael Martin KNAUDER\" GivenName=\"Michael Martin\" Gender=\"M\" TVInitialName=\"M.M. KNAUDER\" FamilyName=\"KNAUDER\" PrintName=\"KNAUDER Michael Martin\" PrintInitialName=\"KNAUDER MM\" Current=\"true\"> <Discipline IFId=\"10081843\" Code=\"EQ\"> <RegisteredEvent Event=\"001\" Class=\"GIA\" Gender=\"X\"> <EventEntry Value=\"H014452\" Type=\"ENTRY\" Code=\"HORSE_ID\"/> <EventEntry Value=\"P 7\" Type=\"ENTRY\" Code=\"PROFILE\"/> </RegisteredEvent> <RegisteredEvent Event=\"401\" Class=\"GIA\" Gender=\"X\"> <EventEntry Value=\"H014452\" Type=\"ENTRY\" Code=\"HORSE\"/> <EventEntry Value=\"P 7\" Type=\"ENTRY\" Code=\"PROFILE\"/> </RegisteredEvent> <RegisteredEvent Event=\"420\" Class=\"GIA\" Gender=\"X\"> <EventEntry Value=\"H014452\" Type=\"ENTRY\" Code=\"HORSE_ID\"/> <EventEntry Value=\"P 7\" Type=\"ENTRY\" Code=\"PROFILE\"/> </RegisteredEvent> </Discipline> </Participant> <Participant Parent=\"1063065\" MainFunctionId=\"TM_OFFIC\" OlympicSolidarity=\"N\" Organisation=\"CZE\" Code=\"1063065\" BirthDate=\"1974-10-28\" Nationality=\"CZE\" Status=\"ACTIVE\" TVName=\"Lenka MATOSKOVA\" GivenName=\"Lenka\" Gender=\"W\" TVInitialName=\"L. MATOSKOVA\" FamilyName=\"MATOSKOVA\" PrintName=\"MATOSKOVA Lenka\" PrintInitialName=\"MATOSKOVA L\" Current=\"true\"> <Discipline Code=\"EQ\"/> </Participant> <Participant Parent=\"1096278\" MainFunctionId=\"AA01\" OlympicSolidarity=\"N\" Organisation=\"AUT\" Code=\"1096278\" BirthDate=\"1995-09-24\" Nationality=\"AUT\" Status=\"ACTIVE\" TVName=\"Julia SCIANCALEPORE\" GivenName=\"Julia\" Gender=\"W\" TVInitialName=\"J. SCIANCALEPORE\" FamilyName=\"SCIANCALEPORE\" PrintName=\"SCIANCALEPORE Julia\" PrintInitialName=\"SCIANCALEPORE J\" Current=\"true\"> <Discipline IFId=\"10108391\" Code=\"EQ\"> <RegisteredEvent Event=\"001\" Class=\"GIA\" Gender=\"X\"> <EventEntry Value=\"H014366\" Type=\"ENTRY\" Code=\"HORSE_ID\"/> <EventEntry Value=\"P 12a\" Type=\"ENTRY\" Code=\"PROFILE\"/> </RegisteredEvent> <RegisteredEvent Event=\"401\" Class=\"GIA\" Gender=\"X\"> <EventEntry Value=\"H014366\" Type=\"ENTRY\" Code=\"HORSE\"/> <EventEntry Value=\"P 12a\" Type=\"ENTRY\" Code=\"PROFILE\"/> </RegisteredEvent> <RegisteredEvent Event=\"420\" Class=\"GIA\" Gender=\"X\"> <EventEntry Value=\"H014366\" Type=\"ENTRY\" Code=\"HORSE_ID\"/> <EventEntry Value=\"P 12a\" Type=\"ENTRY\" Code=\"PROFILE\"/> </RegisteredEvent> </Discipline> </Participant> </Competition> </OdfBody>"; // 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/