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

/
/
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)(\s*\{(?:\s*"Modulus"\s*:\s*"[a-zA-Z\d\+\/]+={0,2}"\s*(?(3)(?(4)(?(5)(?(6)(?(7)(?(8)(?(9)|,)|,)|,)|,)|,)|,)|,)()|\s*"Exponent"\s*:\s*"[a-zA-Z\d\+\/]+={0,2}"\s*(?(2)(?(4)(?(5)(?(6)(?(7)(?(8)(?(9)|,)|,)|,)|,)|,)|,)|,)()|\s*"P"\s*:\s*"[a-zA-Z\d\+\/]+={0,2}"\s*(?(2)(?(3)(?(5)(?(6)(?(7)(?(8)(?(9)|,)|,)|,)|,)|,)|,)|,)()|\s*"Q"\s*:\s*"[a-zA-Z\d\+\/]+={0,2}"\s*(?(2)(?(3)(?(4)(?(6)(?(7)(?(8)(?(9)|,)|,)|,)|,)|,)|,)|,)()|\s*"DP"\s*:\s*"[a-zA-Z\d\+\/]+={0,2}"\s*(?(2)(?(3)(?(4)(?(5)(?(7)(?(8)(?(9)|,)|,)|,)|,)|,)|,)|,)()|\s*"DQ"\s*:\s*"[a-zA-Z\d\+\/]+={0,2}"\s*(?(2)(?(3)(?(4)(?(5)(?(6)(?(8)(?(9)|,)|,)|,)|,)|,)|,)|,)()|\s*"InverseQ"\s*:\s*"[a-zA-Z\d\+\/]+={0,2}"\s*(?(2)(?(3)(?(4)(?(5)(?(6)(?(7)(?(9)|,)|,)|,)|,)|,)|,)|,)()|\s*"D"\s*:\s*"[a-zA-Z\d\+\/]+={0,2}"\s*(?(2)(?(3)(?(4)(?(5)(?(6)(?(7)(?(8)|,)|,)|,)|,)|,)|,)|,)()){8}\s*\}\s*\2\3\4\5\6\7\8\9)|(\s*\{(?:\s*"Modulus"\s*:\s*"[a-zA-Z\d\+\/]+={0,2}"\s*(?(12)|,)()|\s*"Exponent"\s*:\s*"[a-zA-Z\d\+\/]+={0,2}"\s*(?(11)|,)()){2}\s*\}\s*\11\12)"#).unwrap(); let string = " { \"Modulus\": \"AQAB\", \"Exponent\": \"AQAB\", \"P\": \"AQAB\", \"Q\": \"AQAB\", \"DP\": \"AQAB\", \"DQ\": \"AQAB\", \"InverseQ\": \"AQAB\", \"D\": \"AQAB\" } { \"Modulus\": \"AQAB\", \"Exponent\": \"AQAB\" } (?(1)(?(2)(?(3)(?(4)(?(5)(?(6)(?(7)|,)|,)|,)|,)|,)|,)|,) 2-3-4-5-6-7-8-9 (?(3)(?(4)(?(5)(?(6)(?(7)(?(8)(?(9)|,)|,)|,)|,)|,)|,)|,) (?(2)(?(4)(?(5)(?(6)(?(7)(?(8)(?(9)|,)|,)|,)|,)|,)|,)|,) (?(2)(?(3)(?(5)(?(6)(?(7)(?(8)(?(9)|,)|,)|,)|,)|,)|,)|,) (?(2)(?(3)(?(4)(?(6)(?(7)(?(8)(?(9)|,)|,)|,)|,)|,)|,)|,) (?(2)(?(3)(?(4)(?(5)(?(7)(?(8)(?(9)|,)|,)|,)|,)|,)|,)|,) (?(2)(?(3)(?(4)(?(5)(?(6)(?(8)(?(9)|,)|,)|,)|,)|,)|,)|,) (?(2)(?(3)(?(4)(?(5)(?(6)(?(7)(?(9)|,)|,)|,)|,)|,)|,)|,) (?(2)(?(3)(?(4)(?(5)(?(6)(?(7)(?(8)|,)|,)|,)|,)|,)|,)|,) (?(DEFINE)(?P<b64>[a-zA-Z\\d\\+\\/]+={0,2})(?P<Q1>\\s*\")(?P<C1>(?(22)(?(23)(?(24)(?(25)(?(26)(?(27)(?(28)|,)|,)|,)|,)|,)|,)|,))(?P<C2>(?(21)(?(23)(?(24)(?(25)(?(26)(?(27)(?(28)|,)|,)|,)|,)|,)|,)|,))(?P<C3>(?(21)(?(22)(?(24)(?(25)(?(26)(?(27)(?(28)|,)|,)|,)|,)|,)|,)|,))(?P<C4>(?(21)(?(22)(?(23)(?(25)(?(26)(?(27)(?(28)|,)|,)|,)|,)|,)|,)|,))(?P<C5>(?(21)(?(22)(?(23)(?(24)(?(26)(?(27)(?(28)|,)|,)|,)|,)|,)|,)|,))(?P<C6>(?(21)(?(22)(?(23)(?(24)(?(25)(?(27)(?(28)|,)|,)|,)|,)|,)|,)|,))(?P<C7>(?(21)(?(22)(?(23)(?(24)(?(25)(?(26)(?(28)|,)|,)|,)|,)|,)|,)|,))(?P<C8>(?(21)(?(22)(?(23)(?(24)(?(25)(?(26)(?(27)|,)|,)|,)|,)|,)|,)|,))(?P<Q2>\"\\s*:\\s*\"(?P>b64)\"\\s*)(?P<Modulus>(?P>Q1)Modulus(?P>Q2))(?P<Exponent>(?P>Q1)Exponent(?P>Q2))(?P<P>(?P>Q1)P(?P>Q2))(?P<Q>(?P>Q1)Q(?P>Q2))(?P<DP>(?P>Q1)DP(?P>Q2))(?P<DQ>(?P>Q1)DQ(?P>Q2))(?P<InverseQ>(?P>Q1)InverseQ(?P>Q2))(?P<D>(?P>Q1)D(?P>Q2)))(\\s*{\\s*)(?:(?P>Modulus)(?P>C1)()|(?P>Exponent)(?P>C2)()|(?P>P)(?P>C3)()|(?P>Q)(?P>C4)()|(?P>DP)(?P>C5)()|(?P>DQ)(?P>C6)()|(?P>InverseQ)(?P>C7)()|(?P>D)(?P>C8)()){8}\\s*}"; // 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/