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

/
/
s

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"(?s)SQL: \[\d+\] (?<sql>.*) Sent SQL: \[\d+\] (?<send_sql>.*) Params:").unwrap(); let string = "SQL: [126] INSERT INTO `tbl_ip_data` (`ip_start`, `ip_end`, `region_id`, `country_id`, `create_at`) VALUES (:v0d, :v1d, :v2d, :v3d, :v4d) Sent SQL: [163] INSERT INTO `tbl_ip_data` (`ip_start`, `ip_end`, `region_id`, `country_id`, `create_at`) VALUES ('1900145563', '1900145563', '440118', 'CN', '2022-04-15 21:46:42') Params: 5 Key: Name: [4] :v0d paramno=-1 name=[4] \":v0d\" is_param=1 param_type=2 Key: Name: [4] :v1d paramno=-1 name=[4] \":v1d\" is_param=1 param_type=2 Key: Name: [4] :v2d paramno=-1 name=[4] \":v2d\" is_param=1 param_type=2 Key: Name: [4] :v3d paramno=-1 name=[4] \":v3d\" is_param=1 param_type=2 Key: Name: [4] :v4d paramno=-1 name=[4] \":v4d\" is_param=1 param_type=2 [] []"; // 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/