Class

This library provides three different ways to delegate method calls to an object. The easiest to use is SimpleDelegator. Pass an object to the constructor and all methods supported by the object will be delegated. This object can be changed later.

Going a step further, the top level DelegateClass method allows you to easily setup delegation through class inheritance. This is considerably more flexible and thus probably the most common use for this library.

Finally, if you need full control over the delegation scheme, you can inherit from the abstract class Delegator and customize as needed. (If you find yourself needing this control, have a look at Forwardable which is also in the standard library. It may suit your needs better.)

SimpleDelegator’s implementation serves as a nice example of the use of Delegator:

class SimpleDelegator < Delegator
  def __getobj__
    @delegate_sd_obj # return object we are delegating to, required
  end

  def __setobj__(obj)
    @delegate_sd_obj = obj # change delegation object,
                           # a feature we're providing
  end
end

Notes

Be advised, RDoc will not detect delegated methods.

Class Methods

Pass in the obj to delegate method calls to. All methods supported by obj will be delegated to.

Instance Methods
#

Delegates ! to the _getobj_

Returns true if two objects are not considered of equal value.

Returns true if two objects are considered of equal value.

This method must be overridden by subclasses and should return the object method calls are being delegated to.

An alias for raise

This method must be overridden by subclasses and change the object delegate to obj.

Returns true if two objects are considered of equal value.

Freeze both the object returned by _getobj_ and self.

Serialization support for the object returned by _getobj_.

Reinitializes delegation from a serialized object.

Handles the magic of delegation through _getobj_.

Returns the methods available to this delegate object as the union of this object’s and _getobj_ methods.

Returns the methods available to this delegate object as the union of this object’s and _getobj_ protected methods.

Returns the methods available to this delegate object as the union of this object’s and _getobj_ public methods.

Use __raise__ if your Delegator does not have a object to delegate the raise method call.

Checks for a method provided by this the delegate object by forwarding the call through _getobj_.

Taint both the object returned by _getobj_ and self.

Trust both the object returned by _getobj_ and self.

Untaint both the object returned by _getobj_ and self.

Untrust both the object returned by _getobj_ and self.