class CodeRay::Scanners::Ruby::StringState

def self.simple_key_pattern delim
  if delim == "'"
    / (?> (?: [^\\']+ | \\. )* ) ' : /mx
  else
    / (?> (?: [^\\"\#]+ | \\. | \#\$[\\"] | \#\{[^\{\}]+\} | \#(?!\{) )* ) " : /mx
  end
end