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

/
/
gm

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)intensity\"\s*:\s*\(\"\w+\"\s*:\s*(?<intensity>\d+)"#).unwrap(); let string = "(\"data\": [\"from\" : \"2024-04-25T11: 30Z\", \"to\": \"2024-04-2512:00Z\", \"intensity\": (\"forecast\": 152, \"actual\": null, \"index\": \"moderate\"}), (\"from\": \"2024-04-25T12:002\", \"intensity\": {\"forecast\": 152, \"actual\": null, \"index\": \"moderate\"}), (\"from\": \"2024-04-25T12:30Z\", \"to\": {\"from\": \"2024-04-25T13:00Z\", \"to\": \"2024-04-25T12: 30Z\", (\"forecast\": 164, \"actual\": null, \"2024-04-2513: 30Z\", \"intensity\": (\"forecast\": 154, \"to\": \"2024-04-25T13: 002\", \"intensity\": (\"forecast\": 154, \"actual\": null, \"index\": \"actual\": null, \"index\": \"moderate\"}), (\"from\": \"2024-04-25T13:30Z*, \"to\": \"2024-04-25T14:002\", \"moderate\"}}, \"intensity\"： 04-25T14: 30Z\", \"to\" : \"index\": \"moderate\"3}, (\"from\": \"2024-04-25T14:002*, \"to\": \"2024-04-25T14:30Z\", \"intensity\": (\"forecast\": 166, \"actual\": null, \"index\": \"moderate\"}), (\"from\": \" 2024-04-25T15:00Z\" \"actual\": nu11, \"index\" \"intensity\": {\"forecast\": 170, \"actual\": null, \"index\": \"moderate\"}), {\"from\": \"2024-04-2515: 00Z\", 2024- \"to\" : \"moderate\"}), {\"from\": \"2024-04-25T15:30Z\", \"to\": \"2024-04-25T16:00Z\", \"intensity\": (\"forecast\": 175, \"to\": \"2024-04-25T15: 30Z\", \"intensity\": {\"forecast\": 172, \"2024-04-25T16: 30Z\", \"index\": \"moderate\"}}, (\"from\": \"2024-04-25T17:00Z\", \"to\": \"intensity\": (\"forecast\": 177, \"actual\": null, \"index\": \"moderate\"?), (\"from\": \"2024-04-2516: 302\", \"actual\" : nu11, \"index\" \"moderate\"}}, (\"from\": \"2024-04-2516: 00Z\", \"to\": \"2024-04-25T17:002\", \"intensity\": (\"forecast\": 179, \"actual\": null, 2024-04-2517: 30Z\", \"intensity\": (\"forecast\": 181, \"actual\": null, 25T18:00Z\", \"intensity\": (\"forecast\": 184, \"index\": \"moderate\"}}, {\"from\": \"2024-04-25T17: 30Z\", \"actual\": null, \"index\": \"moderate\"}), (\"from\": \"2024-04-25T18:002\", \"to\": \"2024-04-25T18: 30Z\", \"to\": \"2024-04- \"moderate\"}}, (\"from\": \"2024-04-2518: 30Z\", \"to\": \"2024-04-25T19:002\", \"intensity\": (\"forecast\": 187, \"actual\": null, \"intensity\": (\"forecast\": 190, \"actua1\": nul1, \"index\": \"index\": \"high\"}}, (\"from\": \"intensity\": {\"forecast\": 193, \"actual\": null, \"index\": \"2024-04-25T19: 00Z\", \"to\": \"2024-04-25T19: 30Z\" \"high\"}}, (\"from\": \"2024-04-25T19:30Z\", \"to\": \"2024-04-25T20:00Z\", \"intensity\": {\"forecast\": 194, \"2024-04-2520: 00Z\", \"to\": \"2024-04-25T20:30Z\", \"intensity\": {\"forecast\": 195, \"actual\": null, \"index\": \"high\"3}, (\"from\": \"2024-04-25T20:30Z\", \"actual\": null, \"index\": \"high\")}, (\"from\": \"2024-04-25T21:00Z\", \"intensity\": (\"forecast\": 198, \"actual\": null, \"index\": \"high\"'), (\"from\": \"2024-04-25T21: 002\", \"2024-04-25T22: 00Z\", \"intensity\": {\"forecast\": 187, \"actual\": null, \"to\": \"2024-04-25T21: 30Z\", \"intensity\": {\"forecast\": 196, 'actual\": null, \"index\": \"high\"}}, {\"from\": \"2024-04-25T21:302\" \"to\" \"index\": \"moderate\"}}, (\"from\": \"2024-04-25T22:00Z\", \"to\": \"2024-04-25T22: 30Z\", \"intensity\": (\"forecast\": 181, \"actual\": null, \"index\": \"moderate\"}}, {\"from\": \"2024-04-25T22:30Z\", \"to\": \"2024-04-25T23:002\", \"intensity\": (\"forecast\": 180, \"actual\": null, \"index' moderate\"｝｝，｛\"from\"： 25T23:30Z\", \"intensity\": {\"forecast\": 172, \"actual\": null, \"index\": \"moderate\"}}, {\"from\": \"2024-04-25T23: 30Z\", \"2024-04-25T23:002\", \"to\": \" 2024-04- \"moderate\"}}, {\"from\": \"2024-04-26T00:00Z\", \"to\": \"2024-04-2600: 30Z\", \"intensity\": (\"forecast\": 150, \"to\": \"2024-04-2600: 00Z\", \"intensity\": (\"forecast\": 150, \"actual\": null, \"index\": \"actual\": null, \"index\": \"moderate\")}, (\"from\": \"2024-04-26T00: 302\", \"to\": \"2024-04-26T01:00Z\" \"intensity\": {\"forecast\": 149, \"actual\": null, \"index\": \"moderate\"}}, (\"from\": \"2024-04-26T01:002\", \"to\": \"2024-04-26T01:30Z\", \"intensity\": {\"forecast\": 149, \"actual\": null, \"index\": \"moderate\"}}, ..."; // 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/