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

/
/
gms

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#"(?ms)(?:\G|<saml:Attribute\s*+Name="example"[^\/>]*+>)(?:\s*+<saml:AttributeValue\s*+xsi:type="xs:string"[^\/>]*+>(?<value>[^<]*+)<\/saml:AttributeValue[^>]*+>|\s*+<[^\/][^\/>]*+>[^<]*+<\/[^>]*+>|\s*+<[^\/][^>\/]*+\/>)"#).unwrap(); let string = "<samlp:Response xmlns:samlp=\"urn:oasis:names:tc:SAML:2.0:protocol\" xmlns:saml=\"urn:oasis:names:tc:SAML:2.0:assertion\" ID=\"_8e8dc5f69a98cc4c1ff3427e5ce34606fd672f91e6\" Version=\"2.0\" IssueInstant=\"2014-07-17T01:01:48Z\" Destination=\"http://sp.example.com/demo1/index.php?acs\" InResponseTo=\"ONELOGIN_4fee3b046395c4e751011e97f8900b5273d56685\"> <saml:Issuer>http://idp.example.com/metadata.php</saml:Issuer> <samlp:Status> <samlp:StatusCode Value=\"urn:oasis:names:tc:SAML:2.0:status:Success\"/> </samlp:Status> <saml:Assertion xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" xmlns:xs=\"http://www.w3.org/2001/XMLSchema\" ID=\"_d71a3a8e9fcc45c9e9d248ef7049393fc8f04e5f75\" Version=\"2.0\" IssueInstant=\"2014-07-17T01:01:48Z\"> <saml:Issuer>http://idp.example.com/metadata.php</saml:Issuer> <saml:Subject> <saml:NameID SPNameQualifier=\"http://sp.example.com/demo1/metadata.php\" Format=\"urn:oasis:names:tc:SAML:2.0:nameid-format:transient\">_ce3d2948b4cf20146dee0a0b3dd6f69b6cf86f62d7</saml:NameID> <saml:SubjectConfirmation Method=\"urn:oasis:names:tc:SAML:2.0:cm:bearer\"> <saml:SubjectConfirmationData NotOnOrAfter=\"2024-01-18T06:21:48Z\" Recipient=\"http://sp.example.com/demo1/index.php?acs\" InResponseTo=\"ONELOGIN_4fee3b046395c4e751011e97f8900b5273d56685\"/> </saml:SubjectConfirmation> </saml:Subject> <saml:Conditions NotBefore=\"2014-07-17T01:01:18Z\" NotOnOrAfter=\"2024-01-18T06:21:48Z\"> <saml:AudienceRestriction> <saml:Audience>http://sp.example.com/demo1/metadata.php</saml:Audience> </saml:AudienceRestriction> </saml:Conditions> <saml:AuthnStatement AuthnInstant=\"2014-07-17T01:01:48Z\" SessionNotOnOrAfter=\"2024-07-17T09:01:48Z\" SessionIndex=\"_be9967abd904ddcae3c0eb4189adbe3f71e327cf93\"> <saml:AuthnContext> <saml:AuthnContextClassRef>urn:oasis:names:tc:SAML:2.0:ac:classes:Password</saml:AuthnContextClassRef> </saml:AuthnContext> </saml:AuthnStatement> <saml:AttributeStatement> <saml:Attribute Name=\"uid\" NameFormat=\"urn:oasis:names:tc:SAML:2.0:attrname-format:basic\"> <saml:AttributeValue xsi:type=\"xs:string\">test</saml:AttributeValue> </saml:Attribute> <saml:Attribute Name=\"mail\" NameFormat=\"urn:oasis:names:tc:SAML:2.0:attrname-format:basic\"> <saml:AttributeValue xsi:type=\"xs:string\">test@example.com</saml:AttributeValue> </saml:Attribute> <saml:Attribute Name=\"example\" NameFormat=\"urn:oasis:names:tc:SAML:2.0:attrname-format:basic\"> <saml:AttributeValue xsi:type=\"xs:string\">users</saml:AttributeValue> <saml:AttributeValue xsi:type=\"xs:string\">examplerole1</saml:AttributeValue> </saml:Attribute> </saml:AttributeStatement> </saml:Assertion> </samlp:Response>"; // 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/