From: Zach Dennis <zdennis@...>
Date: 2005-07-18T07:11:48+09:00
Subject: Re: alias of some methods does not work

gga wrote:
> irb(main):006:0> module Kernel
> irb(main):007:1>   alias :_methods :methods
> irb(main):008:1> end
> 
> is all OK.
> 
> Yet:
> irb(main):001:0> module Kernel
> irb(main):002:1>  alias :_instance_methods :instance_methods
> irb(main):003:1> end
> NameError: undefined method `instance_methods' for module `Kernel'
>         from (irb):2
>         from :0
> irb(main):004:0> Kernel.instance_methods
> => ["freeze", "__id__", "singleton_methods", ...]
> 
> Is this by design or a bug?  Why can't I alias any of the following:
>   # alias :_constants :constants
>   # alias :_instance_methods :instance_methods
>   # alias :_public_instance_methods :public_instance_methods
>   # alias :_protected_instance_methods :protected_instance_methods
>   # alias :_private_instance_methods :private_instance_methods
> ?

Because those don't belong to Kernel. They belong to the class Module...

irb(main):015:0> class Module
irb(main):016:1> alias :meths :instance_methods
irb(main):017:1> end
=> nil
irb(main):018:0> Module.meths
=> ["send", "name", "class_eval", "object_id", "...etc....

Zach