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

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"(?mx)^ (?<batch_number>\d{2})- (?: (?<component>QQ|CO|CG) (?<target_group>[AS]) (?<paper>P)? ) (?:- (?<domain>(?:LDW|MAT|REA|SCI|XYZ) (?<division>[abc])? ) )? -(?<authoring_point>[TN]) $").unwrap(); let string = "01-COS-SCIa-N 02-COS-SCIb-N 03-COS-SCIc-N 04-QQS-N 05-QQA-N 06-COS-LDW-N 07-COS-XYZ-N 08-CGA-SCI-N 11-COS-MATa-T 12-COS-MATb-T 13-COS-REAa-T 14-COS-REAb-T 15-COS-SCIa-T 16-COS-SCIb-T 17-CGA-SCI-T 18-CGA-MAT-T 19-CGA-REA-T 21-COSP-REAa-T 22-COSP-REAb-T 23-COSP-MATa-T 24-COSP-MATb-T 25-COSP-SCIa-N 26-COSP-SCIa-T 27-QQSP-N 28-QQAP-N 29-COSP-XYZ-N "; // 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/