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

/
/
g

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#"(where|and|or)\s*([^\s=]*?)\s*(=|<>|>=|=<|>|<)\s*("|'|\\"|\\')([^\4]*?)\4"#).unwrap(); let string = "REPLACE active_watchers_log SET sent_msg=\"NOTIFY sip:995582134@192.168.26.5:5062 SIP/2.0 Via: SIP/2.0/UDP 10.23.0.2;branch=z9hG4bKfd9d.445c5656000000000000000000000000.0 To: <sip:995582134@teste.sip.90e9.com>;tag=89b8ace0d56977e7 From: <sip:user_7z7b6s@teste.sip.90e9.com>;tag=9e489e1f14886363a3aeebf53b8dbf2c-4976 CSeq: 34 NOTIFY Call-ID: bec506c8-48da1ac1@192.168.26.5 Content-Length: 277 Max-Forwards: 70 Event: dialog Contact: <sip:10.23.0.2:5060;transport=udp> Subscription-State: active;expires=600 Content-Type: application/dialog-info+xml <?xml version=\\\"1.0\\\"?> <dialog-info xmlns=\\\"urn:ietf:params:xml:ns:dialog-info\\\" version=\\\"34\\\" state=\\\"full\\\" entity=\\\"sip:user_7z7b6s@teste.sip.90e9.com\\\"> <dialog id=\\\"615293b33c62dec073e05d9421e9f48b\\\" direction=\\\"recipient\\\"> <state>terminated</state> </dialog> </dialog-info> \", received_msg=\"SIP/2.0 200 OK To: <sip:995582134@teste.sip.90e9.com>;tag=89b8ace0d56977e7 From: <sip:user_7z7b6s@teste.sip.90e9.com>;tag=9e489e1f14886363a3aeebf53b8dbf2c-4976 Call-ID: bec506c8-48da1ac1@192.168.26.5 CSeq: 34 NOTIFY Via: SIP/2.0/UDP 10.23.0.2;branch=z9hG4bKfd9d.445c5656000000000000000000000000.0 Server: Cisco/SPA504G-7.6.0 Content-Length: 0 \", time=1453481591, result=200 where pres_uri=\"sip:user_7z7b6s@teste.sip.90e9.com\" and callid=\"bec506c8-48da1ac1@192.168.26.5\" and watcher_user=\\\"995582134\\\" and watcher_domain=\\'teste.sip.90e9.com\\' and to_user=\"user_7z7b6s\" and to_domain=\"teste.sip.90e9.com\""; // 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/