From: Charles Oliver Nutter <charles.nutter@...>
Date: 2007-07-13T15:55:40+09:00
Subject: Re: Proposal: runtime-modifying Kernel methods should be keywords

Yukihiro Matsumoto wrote:
> Hi,
> 
> In message "Re: Proposal: runtime-modifying Kernel methods should be keywords"
>     on Fri, 13 Jul 2007 15:42:06 +0900, Charles Oliver Nutter <charles.nutter@sun.com> writes:
> 
> |I'd say anything that fits both of the following criteria qualifies:
> |
> |- the feature can't be implemented without knowing how to manipulate 
> |runtime/implementation-specific structures (and having a way to 
> |manipulate those structures)
> |- the feature can't be wrapped in another method and maintain the same 
> |behavior as if it were called in the original context
> |
> |All those listed so far fit these criteria.
> 
> String#gsub ?

gsub needs access to internal structures (namely, the in-memory 
representation of a String) but it can successfully be wrapped with 
another method. I think both criteria must be met, since being able to 
wrap a method means it's not doing anything weird with the caller's 
logical binding/frame/scope.

class String
   def my_gsub(*x)
     if block_given?
       gsub(*x) {|y| yield y}
     else
       gsub(*x)
     end
   end
end

- Charlie