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)1-0:16\.7\.0\*255":(-?\d+\.?\d+)|1-0:2\.8\.0\*255\":(-?\d+\.?\d+)|1-0:1\.8\.0\*255\":(-?\d+\.?\d+)"#).unwrap(); let string = "{\"meterId\":\"1KFM0000028196\",\"deviceId\":\"EBSD1425009486\",\"msgType\":\"EMETER_OBIS_V2\",\"measurements\":[{\"timestamp\":\"2023-04-02T11:32:33Z\",\"values\":{\"1-0:96.90.2*1\":\"7E2005D2\",\"1-0:0.2.0*0\":\"312E3033\",\"1-0:14.7.0*255\":49.900001525878906,\"1-0:81.7.26*255\":52,\"1-0:81.7.15*255\":331,\"1-0:81.7.4*255\":188,\"1-0:81.7.2*255\":239,\"1-0:81.7.1*255\":117,\"1-0:71.7.0*255\":1.1100000143051147,\"1-0:51.7.0*255\":0.73000001907348633,\"1-0:31.7.0*255\":1.8999999761581421,\"1-0:72.7.0*255\":235.5,\"1-0:52.7.0*255\":233.80000305175781,\"1-0:32.7.0*255\":235.89999389648438,\"1-0:16.7.0*255\":-152,\"1-0:2.8.0*255\":0.52590000629425049,\"1-0:1.8.0*255\":10474.70703125,\"1-0:96.1.0*255\":\"0A014B464D0000006E24\",\"1-0:96.50.1*1\":\"4B464D\"}}]}"; // 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/