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"((?:\\033|\e|\\x1B|\\x1b){1}(?:\[(?:=|\?|[0-9]*)[0-9]*[a-gA-GnmsuJKhlHL]{0,1}(?:(?:\;[0-9]*)*m){0,1}))").unwrap(); let string = "0x7ffff00196a0 \"\\r\\r\\r\\033[9999B[\\033[m\\033[36madmin\\033[m@\\033[m\\033[32mLeonards_switch\\033[m] > \" \\r routerboard: yes\\r\\n model: CRS112-8P-4S\\r\\n revision: r2\\r\\n serial-number: F1 4F0FC0637C\\r\\n firmware-type: qca8513 L \\r \\n f a c t o r y - f i r m w a r e : 6 . 4 7 . 1 0 \\r \\n c u r r e n t - f i r m w a r e : 6 . 4 7 . 1 0 \\r \\n u p g r a d e - f i r m w a r e : 6 . 4 7 . 1 0 \\r \\x1b[1;31mHello \\x1b[2;37;41mWorld \\033[38;2;1;22;252m \\033[38;5;5m \\033[48;5;5m \\033[48;2;15;251;3m \\033[0J \\033[J \\033[1J \\033[3J \\033[K \\033[0K \\033[u \\033[s \\033[8 \\033[7 \\033[m \\033[6n \\033[5G \\033[=14h \\033[=15l \\033[?25h \\033[?1049l"; // 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/