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)1-0:1.8.2\(([0-9]{1,96}).([0-9]{1,96}).*(kWh)").unwrap(); let string = "/KFM5KAIFA-METER 1-3:0.2.8(42) 0-0:1.0.0(230312193138W) 0-0:96.1.1(4530303235313030303635313836373136) 1-0:1.8.1(010971.897*kWh) 1-0:1.8.2(016085.943*kWh) 1-0:2.8.1(000000.000*kWh) 1-0:2.8.2(000000.000*kWh) 0-0:96.14.0(0001) 1-0:1.7.0(00.404*kW) 1-0:2.7.0(00.000*kW) 0-0:96.7.21(00003) 0-0:96.7.9(00004) 1-0:99.97.0(5)(0-0:96.7.19)(221209092021W)(0000004031*s)(210314223749W)(0000000455*s)(210207175517W)(0000003289*s)(180331043234S)(0000000398*s)(000101000001W)(2147483647*s) 1-0:32.32.0(00000) 1-0:32.36.0(00000) 0-0:96.13.1() 0-0:96.13.0() 1-0:31.7.0(002*A) 1-0:21.7.0(00.390*kW) 1-0:22.7.0(00.000*kW) !2284 "; // 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/