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

Generated Code

re = /await[\t\f\v ]+((?:[^(),\n\]\[]*(?:\((?:[^()\n]|(?:(?:\([^()\n]*\))*|\((?:[^()\n]|(?:(?:\([^()\n]*\))*))*\)))*\))*)+)/ str = 'const one = [await 1, await 2]\', const three = await \\\'1\\\'\', const four = await async function a() { }\', const five = await Promise.resolve(5, 2)\', const six = await Promise.resolve([Promise.resolve(1), Promise.resolve(2)])\', const seven = await requestAsPromise.get(\\\'https://jsonplaceholder.typicode.com/test/1\\\').body, const eight = await Promise.all([Promise.resolve(1), Promise.reject(2)]), const nine = await new Promise((resolve, reject) => { resolve(3) }), const ten = await new Cache().save(), const eleven = await Promise.all([co(gen())])' # Print the match result str.scan(re) do |match| puts match.to_s end

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 Ruby, please visit: http://ruby-doc.org/core-2.2.0/Regexp.html