From: Ken Bloom <kbloom@...>
Date: 2006-09-09T01:45:14+09:00
Subject: Re: BEST alias_method Re: [CHALLENGE] better alias_method

On Sat, 09 Sep 2006 01:17:46 +0900, ara.t.howard wrote:

> On Sat, 9 Sep 2006, Jason Nordwick wrote:
> 
>> The best alias_method methods would be one that didn't exist. 
>> (1) It encourages breaking of naming conventions since at times two functions 
>> get defined, one with the convension and one without, (see hash.merge! and 
>> hash.update), and I really liked the convention where mutatations have bangs 
>> at the end.
>>
>> (2) This one function double the complexity of learning to read ruby. Now I 
>> don't just have to know what hash.update does, but also that hash.merge! is 
>> the same thing. And when individual developers start adding aliases to 
>> buildins things get ever worse. Array.lower isn't necessary when Array.first 
>> and Array[0] are both as short or shorter and just as descriptive.
>>
>> Alaises increase complexity and really are one of Ruby's biggest dislikes for 
>> me.
> 
> the primary reason to use aliases is not to simply have another handle on
> names - but override or wrap a method for instance.
> 
>    require 'sync'
> 
>    class Module
>      def ex m
>        module_eval{
>          include Sync_m
>          alias_method "__#{ m }__", "#{ m }"
>        }
>        module_eval <<-code
>          def #{ m } *a, &b
>            synchronize{ __#{ m }__ *a, &b }
>          end
>        code
>      end
>    end
> 
> 
>    class C
>      def foobar
>        42
>      end
> 
>      ex :foobar
>    end
> 
> 
> if you do much metaprogramming and/or dsl contruction you find, in a matter of
> seconds, that alias_method is essential.  i think most people find the
> declarative style of class methods as syntax (think 'attr',
> 'has_and_belongs_to_many', etc) to be one of ruby's best features.
> unfortunately it oftern hinges on alias_method which has issues if a cycle is
> setup.

The solution to this problem will actually let alias_method fall into
disuse faster, since we don't need to use alias_method directly to wrap or
override an old method anymore.

--Ken

-- 
Ken Bloom. PhD candidate. Linguistic Cognition Laboratory.
Department of Computer Science. Illinois Institute of Technology.
http://www.iit.edu/~kbloom1/