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
Processing...

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#"(\w+\s+\d{1,2}\s+\d\d:\d\d:\d\d)\s+([a-zA-Z0-9\-]+)\s+[SFIMS:]{1,6}\s+\[([a-zA-Z0-9_\s]+)\s+\(([0-9a-z\-]+)\)\]\[(.+)\]\[(([0-9]+)\:([0-9]+)\:[0-9]+)\]\s+\"(.+)\"\s+\[Classification\:\s+(.+)\]\s+User\:\s+(.+)\,\s+Application\:\s+(.+)\,\s+Client:\s+(.+)\,\s+App Protocol\:\s+(.+)\,\s+Interface Ingress\:\s+([a-zA-Z\-\_0-9]+)\,\s+Interface Egress\:\s+([a-zA-Z\-\_0-9]+)\,\s+Security Zone Ingress\:\s+([a-zA-Z\-\_0-9]+)\,\s+Security Zone Egress\:\s+([a-zA-Z\-\_0-9]+)\,\s+Context\:\s+([a-zA-Z\-\_0-9]+)\,\s+\[Priority\:\s+([0-9]+)\]\s+\{([A-Z]+)\}\s+([0-9.]+):([0-9]+)\s->\s([0-9.]+):([0-9]+)"#).unwrap(); let string = "Aug 7 17:47:38 Sourcefire3D SFIMS: [Primary Detection Engine (b363fd8a-2ec5-11de-91d7-e63c5c5fcc50)][ZurichConnect _ Osservazione][1:402:15] \"PROTOCOL-ICMP Destination Unreachable Port Unreachable\" [Classification: Misc Activity] User: Unknown, Application: Unknown, Client: Unknown, App Protocol: Unknown, Interface Ingress: s1p3, Interface Egress: s1p4, Security Zone Ingress: Internal, Security Zone Egress: External, Context: Unknown, SSL Flow Status: N/A, SSL Actual Action: N/A, SSL Certificate: 0000000000000000000000000000000000000000, SSL Subject CN: N/A, SSL Subject Country: N/A, SSL Subject OU: N/A, SSL Subject Org: N/A, SSL Issuer CN: N/A, SSL Issuer Country: N/A, SSL Issuer OU: N/A, SSL Issuer Org: N/A, SSL Valid Start Date: N/A, SSL Valid End Date: N/A, [Priority: 3] {ICMP} 172.23.33.201 -> 172.23.34.74, type: Destination Unreachable, code: Port unreachable"; // result will be a tuple containing the start and end indices for the first match in the string let result = regex.captures(string); let (start, end) = match result { Some((s, e)) => (s, e), None => { // ... } }; println!("{}", &string[start, end]); }

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/