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]
  • Character class intersection
    [\w&&[^\d]]
  • 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
Processing...

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#"(?ms)(?:<!\[CDATA\[(?<cdata>.*?)\]\]>|(?<xml><\?.*?\?>)|<!--(?<comment>.*?)-->|<\s*(?<tag>[A-z][A-z0-9-_.:]*)(?:\s+(?:[A-z][A-z0-9-_.:]*)\s*(?:=\s*(?<quote>["'])((?:\\\k<quote>|(?:(?!\k<quote>)).)*)(\k<quote>)\s*)?)*\s*(?:/\s*>|>(?<innerHTML>.*)?<\s*/\s*\k<tag>\s*>)|(?<text>[^<]*))"#).unwrap(); let string = "<?xml version='1.0' encoding='shift_jis'?> <!-- foo --> <foo>bar</foo> Baz <foo asdf=\"foo\" /> <CharacterInfo defaultUid=''> <Character name='??????' uid='511111' weapon='??' HR='7' GR='0' lastLogin='1645561498' sex='M' /> <Character name ='Potatoe/>sss' uid= '511111' weapon = '??' HR='7' GR=\"0\" lastLogin='1645561498' sex='M' /> </CharacterInfo> Plain text <hr/> Multi line text <br /> <!-- This is a comment! <foo /> --> <foo bar/> <baz asdf=\"2\"></baz> <asd foo=\"asd\\\"q'we\" / > <b>Hello, <i>World</i>!</b> <Character name='??????' uid='511111' weapon='??' HR='7' GR='0' lastLogin='1645561498' sex='M' /> <Character name ='Potatoe/>sss' uid= '511111' weapon = '??' HR='7' GR=\"0\" lastLogin='1645561498' sex='M' /> <![CDATA[]]> <![CDATA[Foobar<>]]> <![CDATA[ asdasdasd adsd sd sd ]]> "; // 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/