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#"(\s|\S){0,40}\"([0-9]{1,3})\"\;\}"#).unwrap(); let string = "a:1:{s:2:\"gr\";s:3:\"214\";} a:1:{s:2:\"gr\";s:3:\"188\";} a:1:{s:2:\"gr\";s:3:\"213\";} a:1:{s:2:\"gr\";s:3:\"169\";} a:1:{s:2:\"gr\";s:3:\"219\";} a:1:{s:2:\"gr\";s:3:\"221\";} a:1:{s:2:\"gr\";s:3:\"211\";} a:1:{s:2:\"gr\";s:3:\"184\";} a:1:{s:2:\"gr\";s:3:\"191\";} a:1:{s:2:\"gr\";s:2:\"16\";} a:1:{s:2:\"gr\";s:3:\"127\";} a:1:{s:2:\"gr\";s:3:\"217\";} a:1:{s:2:\"gr\";s:3:\"200\";} a:1:{s:2:\"gr\";s:3:\"182\";} a:1:{s:2:\"gr\";s:3:\"128\";} a:1:{s:2:\"gr\";s:2:\"17\";} a:1:{s:2:\"gr\";s:3:\"163\";} a:1:{s:2:\"gr\";s:3:\"212\";} a:1:{s:2:\"gr\";s:3:\"166\";} a:1:{s:2:\"gr\";s:2:\"94\";} a:1:{s:2:\"gr\";s:2:\"83\";} a:1:{s:2:\"gr\";s:2:\"27\";} a:1:{s:2:\"gr\";s:2:\"28\";} a:1:{s:2:\"gr\";s:3:\"167\";} a:1:{s:2:\"gr\";s:3:\"168\";} a:1:{s:2:\"gr\";s:3:\"202\";} a:1:{s:2:\"gr\";s:1:\"7\";} a:1:{s:2:\"gr\";s:3:\"129\";} a:1:{s:2:\"gr\";s:3:\"183\";} a:1:{s:2:\"gr\";s:2:\"26\";} a:1:{s:2:\"gr\";s:3:\"185\";} a:1:{s:2:\"gr\";s:3:\"175\";} a:1:{s:2:\"gr\";s:2:\"29\";} a:1:{s:2:\"gr\";s:3:\"209\";} a:1:{s:2:\"gr\";s:3:\"177\";} a:1:{s:2:\"gr\";s:3:\"178\";} a:1:{s:2:\"gr\";s:2:\"24\";} a:1:{s:2:\"gr\";s:3:\"225\";} a:1:{s:2:\"gr\";s:3:\"224\";} a:1:{s:2:\"gr\";s:2:\"57\";} a:1:{s:2:\"gr\";s:2:\"18\";} a:1:{s:2:\"gr\";s:3:\"208\";} a:1:{s:2:\"gr\";s:3:\"193\";} a:1:{s:2:\"gr\";s:2:\"33\";} a:1:{s:2:\"gr\";s:2:\"10\";} a:1:{s:2:\"gr\";s:2:\"11\";} a:1:{s:2:\"gr\";s:2:\"12\";} a:1:{s:2:\"gr\";s:3:\"173\";} a:1:{s:2:\"gr\";s:2:\"13\";} a:1:{s:2:\"gr\";s:2:\"14\";} a:1:{s:2:\"gr\";s:1:\"9\";} a:1:{s:2:\"gr\";s:2:\"15\";} a:1:{s:2:\"gr\";s:3:\"195\";} a:1:{s:2:\"gr\";s:3:\"130\";} a:1:{s:2:\"gr\";s:2:\"25\";} a:1:{s:2:\"gr\";s:2:\"50\";} a:1:{s:2:\"gr\";s:3:\"131\";} a:1:{s:2:\"gr\";s:2:\"96\";} a:1:{s:2:\"gr\";s:2:\"19\";} a:1:{s:2:\"gr\";s:3:\"107\";} a:1:{s:2:\"gr\";s:3:\"116\";} a:1:{s:2:\"gr\";s:3:\"364\";} a:1:{s:2:\"gr\";s:3:\"194\";} a:1:{s:2:\"gr\";s:2:\"44\";} a:1:{s:2:\"gr\";s:3:\"171\";} a:1:{s:2:\"gr\";s:3:\"172\";} a:1:{s:2:\"gr\";s:3:\"170\";} a:1:{s:2:\"gr\";s:2:\"20\";} a:1:{s:2:\"gr\";s:2:\"95\";} a:1:{s:2:\"gr\";s:2:\"84\";} a:1:{s:2:\"gr\";s:2:\"22\";} a:1:{s:2:\"gr\";s:2:\"23\";} a:1:{s:2:\"gr\";s:2:\"67\";} a:1:{s:2:\"gr\";s:3:\"118\";} a:1:{s:2:\"gr\";s:2:\"97\";} a:1:{s:2:\"gr\";s:1:\"6\";} a:1:{s:2:\"gr\";s:3:\"365\";} a:1:{s:2:\"gr\";s:3:\"190\";} a:1:{s:2:\"gr\";s:2:\"82\";} a:1:{s:2:\"gr\";s:2:\"42\";} a:1:{s:2:\"gr\";s:2:\"74\";} a:1:{s:2:\"gr\";s:2:\"76\";} a:1:{s:2:\"gr\";s:2:\"73\";} a:1:{s:2:\"gr\";s:2:\"78\";} a:1:{s:2:\"gr\";s:2:\"68\";} a:1:{s:2:\"gr\";s:3:\"207\";} a:1:{s:2:\"gr\";s:3:\"197\";} a:1:{s:2:\"gr\";s:2:\"77\";} a:1:{s:2:\"gr\";s:2:\"46\";} a:1:{s:2:\"gr\";s:2:\"51\";} a:1:{s:2:\"gr\";s:3:\"206\";} a:1:{s:2:\"gr\";s:3:\"165\";} a:1:{s:2:\"gr\";s:2:\"60\";} a:1:{s:2:\"gr\";s:2:\"61\";} a:1:{s:2:\"gr\";s:2:\"62\";} a:1:{s:2:\"gr\";s:3:\"187\";} a:1:{s:2:\"gr\";s:3:\"176\";} a:1:{s:2:\"gr\";s:3:\"196\";} a:1:{s:2:\"gr\";s:3:\"223\";} a:1:{s:2:\"gr\";s:3:\"117\";} a:1:{s:2:\"gr\";s:2:\"98\";} a:1:{s:2:\"gr\";s:2:\"47\";} a:1:{s:2:\"gr\";s:3:\"198\";} a:1:{s:2:\"gr\";s:2:\"45\";} a:1:{s:2:\"gr\";s:3:\"203\";} a:1:{s:2:\"gr\";s:3:\"205\";} a:1:{s:2:\"gr\";s:3:\"201\";} a:1:{s:2:\"gr\";s:3:\"115\";} a:1:{s:2:\"gr\";s:2:\"58\";} a:1:{s:2:\"gr\";s:3:\"204\";} a:1:{s:2:\"gr\";s:3:\"132\";} a:1:{s:2:\"gr\";s:2:\"48\";} a:1:{s:2:\"gr\";s:2:\"49\";} a:1:{s:2:\"gr\";s:2:\"99\";} a:1:{s:2:\"gr\";s:3:\"594\";} a:1:{s:2:\"gr\";s:3:\"585\";} a:1:{s:2:\"gr\";s:3:\"368\";} a:1:{s:2:\"gr\";s:2:\"81\";} a:1:{s:2:\"gr\";s:2:\"53\";} a:1:{s:2:\"gr\";s:2:\"52\";} a:1:{s:2:\"gr\";s:3:\"180\";} a:1:{s:2:\"gr\";s:3:\"181\";} a:1:{s:2:\"gr\";s:3:\"179\";} a:1:{s:2:\"gr\";s:3:\"164\";} a:1:{s:2:\"gr\";s:3:\"186\";} a:1:{s:2:\"gr\";s:3:\"174\";} a:1:{s:2:\"gr\";s:3:\"199\";} a:1:{s:2:\"gr\";s:3:\"210\";} a:1:{s:2:\"gr\";s:3:\"369\";} a:1:{s:2:\"gr\";s:3:\"370\";} a:1:{s:2:\"gr\";s:3:\"371\";} a:1:{s:2:\"gr\";s:3:\"372\";} a:1:{s:2:\"gr\";s:3:\"373\";} a:1:{s:2:\"gr\";s:3:\"374\";} a:1:{s:2:\"gr\";s:3:\"375\";}"; // 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/