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

r"
"
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)(?:(?:^edit\ \"(.+)\"$\n)(?:^set\ uuid\ ([a-f0-9]{8}\-(?:[a-f0-9]{4}\-){3}[a-f0-9]{12})$\n)(?:(?:^set\ comment\ )((?:(?!^set\ )(?:.*$\n))+)(?=^set\ ))?(?:^set\ service\ (\".+\")$\n)?(?:^set\ extip\ ((?:(?:\d{1,3}\.){3}(?:\d{1,3}))(?:\-(?:\d{1,3}\.){3}(?:\d{1,3}))?)$\n)(?:^set\ extintf\ \"(.+)\"$\n)(?:^(set\ portforward)\ (enable)$\n)?(?:^(set\ color)\ (\d{1,2})$\n)?(?:^set\ mappedip\ \"((?:(?:\d{1,3}\.){3}(?:\d{1,3}))(?:\-(?:\d{1,3}\.){3}(?:\d{1,3}))?)\"$\n)(?:^(set\ protocol)\ (.+)$\n)?(?:^(set\ extport)\ (\d{1,5}(?:\-\d{1,5})?)$\n)?(?:^(set\ mappedport)\ (\d{1,5}(?:\-\d{1,5})?)$\n)?(?:^next$\n(?:^$\n)?))"#).unwrap(); let string = "edit \"VIP [DNS сервер site.com]\" set uuid abcdef01-2345-6789-abcd-ef0123456789 set comment \"Публикация IP-адреса для проекта \\\"TEST\\\" в ДЦ \\\"Облако\\\"\" set service \"HTTP Webserver\" set extip 100.200.254.20 set extintf \"DMZ [VLAN 100]\" set portforward enable set color 3 set mappedip \"10.100.200.5\" set protocol udp set extport 53 set mappedport 2000-65535 next edit \"VIP [NTP сервер site.com]\" set uuid abcdef01-2345-6789-abcd-ef0123456789 set comment \"Публикация IP-адреса для проекта \\\"TEST\\\" в ДЦ \\\"Облако\\\"\" set service \"NTP TCP Server\" \"NTP UDP Server\" set extip 100.200.254.20-100.200.254.21 set extintf \"DMZ [VLAN 100]\" set portforward enable set color 3 set mappedip \"10.100.200.5-10.100.200.6\" set protocol udp set extport 123 set mappedport 1000-1999 next "; // 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/