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

/
/

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"TR\$.+?(?=\n)").unwrap(); let string = "TR$1b3abc T0b0 4 0 20151117 062231 7 14 15 c0a81e03 0 0 1 00A 3 481915101 3 481915101 0 1 3 90047975097350 001 0 3 975097350 1 9 F10 XT 131550-251897 FT110393_RT43 loop[gw_sip,PR970149981] 0 D00c 3108 222e42 E007 020103 H018 3 481915101 10 TRAFTERM G033 20151117 06223185 0000000050 0000000772 0000001484 V013 0 20 0 0 0 SIP_OUT O038 7109 58056 56252 354 343 0 4 0 IP2TDM 192.168.31.6:6372 Z02c 20925-DY-0001b6a8-523106f36@sip.mystream.fr GO$18c T0a3 185 0 20151117 063030 6 17 18 c0a81e03 1 0 1 00A 3 139947700 3 139947752 0 1 3 629452310 001 0 3 629452310 1 24 B10 XT 265720-251900 SIP loop[gw_sip,PEER_SFR_2] 0 D00c 3108 222e48 G033 20151117 06303070 0000000071 0000001140 0000001731 L008 1 1 3 1 E007 020103 Y005 3 15 V012 8 20 0 0 0 SIP_IN V013 8 20 0 0 0 SIP_OUT Z02c 21325-EZ-0001b7ed-3b997c5d2@sip.mystream.fr Z00d 70b7375a@pbx"; // result will be a tuple containing the start and end indices for the first match in the string let result = regex.captures(string); let (start, end) = match result { Some((s, e)) => (s, e), None => { // ... } }; println!("{}", &string[start, end]); }

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/