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

/
/
sg

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"(?s)<(?<key>[^>]+)>(?<value>[^<]+)<\/\1>").unwrap(); let string = "[2015-08-10T15:00:03.644+1000] | INFO | cessAuditorEvent | updateNetworkResource | 188 - ib2b-common-lib - 3.0.4074 | 1c679b99-2235-4027-93a5-9f9b91822c77 | 9e9 ib2b-bs-manage-network-resource_3.0.4074 WorkforceManagement NBNTEST01 ? HEADER [activityName=\"updateNetworkResource\", msgName=\"ManageNetworkResourceupdateNetworkResourceError\", businessServiceName=\"ManageNetworkResource\", businessServiceVersion=\"V1.0\", msgType=\"Error\", accessSeekerId=\"NBNTEST01\", replyToURI=\"SERVICE.BS.MANAGE_NETWORK_RESOURCE.V1.RESP.WWM\", activityStatus=\"Failure\", correlationId=\"1c679b99-2235-4027-93a5-9f9b91822c77\", security=\"Placeholder Security\", priority=\"4\", communicationPattern=\"RequestReply\", timestamp=\"2015-08-10T05:00:03Z\", businessChannel=\"WorkforceManagement\", headerCharacteristicValue=\"[Mocked:TRUE]\"] MESSAGE [<?xml version=\"1.0\" encoding=\"UTF-8\"?><soapenv:Fault xmlns:soapenv=\"http://schemas.xmlsoap.org/soap/envelope/\" xmlns:exp=\"http://www.nbnco.com.au/cim/common/exception/v5\" xmlns:xs=\"http://www.w3.org/2001/XMLSchema\" xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" xmlns:nbnfn=\"http://www.nbnco.com.au/functions\"><faultcode>exp:TechnicalException</faultcode><faultstring>000000: A technical error has occurred during the processing of the request.</faultstring><detail><exp:TechnicalException><Exception><ID>000000</ID><description>A technical error has occurred during the processing of the request.</description><type>Error</type><ReferencesApplicationException><returnType>Technical</returnType><returnCode>PNI-TEC-0003</returnCode><returnDescription>A data issue has prevented the application from processing the request.</returnDescription></ReferencesApplicationException></Exception></exp:TechnicalException></detail></soapenv:Fault>] [jms://queue:SERVICE.BS.MANAGE_NETWORK_RESOURCE.V1.RESP.WWM (12ms taken)] [ExchangeSentEvent]"; // 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/