Class: Object

Inherits:
BasicObject
Defined in:
lib/functional/behavior.rb

Instance Method Summary collapse

Instance Method Details

#behaves_as?(name, abend = false) ⇒ Boolean

Note:

Will return true if the object implements the required methods. The object’s class hierarchy does not necessarily have to include a corresponding #behavior call.

Does the object implement the given #behavior_info?

Parameters:

  • name (Symbol) —

    name of the #behavior_info to verify behavior against.

  • abend (Boolean) (defaults to: false) —

    raise an exception when true and the there are unimplemented methods

Returns:

  • (Boolean) —

    whether or not the required public methods are implemented



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# File 'lib/functional/behavior.rb', line 97

def behaves_as?(name, abend = false)

  name = name.to_sym
  bi = $__behavior_info__[name]
  return false if bi.nil?

  validator = proc do |obj, method, arity|
    (obj.respond_to?(method) && arity == :any) || obj.method(method).arity == arity
  end

  if self.is_a?(Class) || self.is_a?(Module)
    bi = bi.select{|method, arity| method.to_s =~ /^self_/ }
  end

  bi.each do |method, arity|
    begin
      func = method.to_s
      obj = self

      if (self.is_a?(Class) || self.is_a?(Module)) && func =~ /^self_/
        func = func.gsub(/^self_/, '')
      elsif method =~ /^self_/
        func = func.gsub(/^self_/, '')
        obj = self.class
      end

      valid = validator.call(obj, func, arity)
      raise NameError if abend && ! valid
      return valid unless valid
    rescue NameError
      if abend
        func = "#{method.to_s.gsub(/^self_/, 'self.')}/#{arity.to_s.gsub(/^any$/, ':any')}"
        raise BehaviorError.new("undefined callback function ##{func} in #{self} (behavior '#{name}')")
      else
        return false
      end
    end
  end

  return true
end