Regular Expressions 101

Save & Manage Regex

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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"(?m)(?:\d*\.)?\d+$").unwrap(); let string = " 22/09/2015 11:05:41 | Dispense complete for COTTON, final dispense weight was 0.0262 22/09/2015 11:08:02 | Dispense complete for COTTON, final dispense weight was 0.0264 22/09/2015 11:10:08 | Dispense complete for COTTON, final dispense weight was 0.0229 22/09/2015 11:12:03 | Dispense complete for COTTON, final dispense weight was 0.0188 22/09/2015 11:14:22 | Dispense complete for COTTON, final dispense weight was 0.0292 22/09/2015 11:16:48 | Dispense complete for COTTON, final dispense weight was 0.0245 22/09/2015 11:18:37 | Dispense complete for COTTON, final dispense weight was 0.0243 22/09/2015 11:20:56 | Dispense complete for COTTON, final dispense weight was 0.0261 22/09/2015 11:22:53 | Dispense complete for COTTON, final dispense weight was 0.0228 22/09/2015 11:24:43 | Dispense complete for COTTON, final dispense weight was 0.0204 22/09/2015 11:26:38 | Dispense complete for COTTON, final dispense weight was 0.0223 22/09/2015 11:28:29 | Dispense complete for COTTON, final dispense weight was 0.0257 22/09/2015 11:30:20 | Dispense complete for COTTON, final dispense weight was 0.0371 22/09/2015 11:32:14 | Dispense complete for COTTON, final dispense weight was 0.0376 22/09/2015 11:36:18 | Dispense complete for COTTON, final dispense weight was 0.0222 22/09/2015 11:39:28 | Dispense complete for COTTON, final dispense weight was 0.0234 22/09/2015 11:41:23 | Dispense complete for COTTON, final dispense weight was 0.0255 22/09/2015 11:43:24 | Dispense complete for COTTON, final dispense weight was 0.0242 22/09/2015 11:46:30 | Dispense complete for COTTON, final dispense weight was 0.0354 22/09/2015 11:50:04 | Dispense complete for COTTON, final dispense weight was 0.0294"; // 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/