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

/
/
g

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"([\d]{2}\/[\d]{2}\/[\d]{4})[\s]([\d]{2}:[\d]{2}:[\d]{2}\.[\d]{2})\sid:\s([\d]{4})\sseq:\s([\d]{4})[\s<>]*type:\s([\da-f]{4})\slen:[\s]*([\d]{2})\s([\w]*)").unwrap(); let string = "05/23/2017 14:19:57.96 id: 0001 seq: 0001 < type: 0009 len: 10 CMD_CHECK_PROTOCOL version: 7 05/23/2017 14:19:57.96 id: 0001 seq: 0001 > type: 8001 len: 72 ANS_OK 05/23/2017 14:19:58.07 id: 0001 seq: 0002 < type: 0001 len: 91 CMD_AUTH sender: 0 type: 4 id: 'admin' 05/23/2017 14:19:58.07 id: 0001 seq: 0002 > type: 8002 len: 10 ANS_ERR err_code: 0x1 05/23/2017 14:19:58.07 id: 0001 seq: 0001 > type: 000f len: 12 CMD_DISCONNECT reason: 3 05/23/2017 14:20:01.91 id: 0002 seq: 0003 < type: 0009 len: 10 CMD_CHECK_PROTOCOL version: 7 05/23/2017 14:20:01.91 id: 0002 seq: 0003 > type: 8001 len: 72 ANS_OK 05/23/2017 14:20:01.92 id: 0002 seq: 0004 < type: 0001 len: 91 CMD_AUTH sender: 0 type: 4 id: 'admin' 05/23/2017 14:20:01.92 id: 0002 seq: 0004 > type: 8002 len: 10 ANS_ERR err_code: 0x1 05/23/2017 14:20:01.92 id: 0002 seq: 0001 > type: 000f len: 12 CMD_DISCONNECT reason: 3 05/23/2017 14:24:53.27 id: 0003 seq: 0001 < type: 0009 len: 10 CMD_CHECK_PROTOCOL version: 7 05/23/2017 14:24:53.27 id: 0003 seq: 0001 > type: 8001 len: 72 ANS_OK 05/23/2017 14:24:53.32 id: 0003 seq: 0002 < type: 0001 len: 91 CMD_AUTH sender: 0 type: 4 id: 'Admin' 05/23/2017 14:24:53.32 id: 0003 seq: 0002 > type: 8001 len: 15 ANS_OK 05/23/2017 14:24:53.37 id: 0003 seq: 0003 < type: 0100 len: 16 CMD_USER_LIST limit: 0 offset: 0 05/23/2017 14:24:53.37 id: 0003 seq: 0003 > type: 8001 len: 499 ANS_OK 05/23/2017 14:24:53.40 id: 0003 seq: 0004 < type: 000d len: 10 CMD_SVR_GET_PARAMS parameter_id: 0"; // 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/