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

/
/
gmi

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"(?mi)(^\w+\s?\D+)\s?(\d+[,\d+]*)\s?(\d+[,\d+]*)\s?(\d+[,\d+]*)\s?(\d+[,\d+]*)\s?(\d+[,\d+]*)\s?").unwrap(); let string = "Weapon Type/Force Used 2000 2001 2002 2003 2004 5-Year Total Personal Weapons 12,945 17,830 20,636 21,933 25,050 98,394 None 2,702 3,114 2,974 3,294 4,176 16,260 Other 1,775 2,311 2,332 2,420 2,842 11,680 Knife/Cutting Instrument 1,511 2,082 2,080 2,445 2,852 10,970 Handgun 307 376 398 430 497 2,008 Blunt Object 283 404 394 455 469 2,005 Firearm (type not stated) 94 131 103 135 146 609 Other Firearm 74 107 92 155 154 582 Explosives 145 139 93 89 95 561 Motor Vehicle 43 52 46 59 71 271 Fire/Incendiary Device 36 34 42 36 88 236 Rifle 23 33 33 24 37 150 Shotgun 15 24 30 19 24 112 Drugs/Narcotics/Sleeping Pills 9 4 8 14 6 41 Poison 1 8 4 11 16 40 Asphyxiation 2 1 3 6 2 14 "; // 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/