def is_version(string)
      return false if string === false || string === true || string.nil?
      string.to_s.match(/^\d+[\d\.a-zA-Z\-_~]*/)
    end
def is_version(string)
      return false if string === false || string === true || string.nil?
      string.to_s.match(/^\d+[\d\.a-zA-Z\-_~]*/)
    end
Returns `true` if provided value is a version string
 @param string [String, Symbol] value to check
 @return [TrueClass, FalseClass]