From: "David A. Black" <dblack@...>
Date: 2008-10-07T22:42:34+09:00
Subject: [ruby-core:19162] Re: [Feature #615] "with" operator

Hi --

On Tue, 7 Oct 2008, Gary Wright wrote:

>
> On Oct 7, 2008, at 6:06 AM, David A. Black wrote:
>> It's not so much a scope thing as a 'self' thing. My understanding is
>> that it would produce a context where this happens:
>>
>>  m   # sent to one object
>>  @v  # instance variable of a different object
>
> It seemed to me that something different was being proposed. During
> the execution of the block, the object associated with 'self' is
> augmented with additional methods.  When the block finishes the
> additional methods are withdrawn.  It isn't the message dispatch
> mechanism that is changing but instead the included module list of
> the object's singleton class is being temporarily modified.
>
> So in your example, 'm' and '@v' are still evaluated relative to
> the same 'self'.

OK, I probably got it wrong.

It sounds somewhat similar to import-module[1], which lets you do
block-wise module inclusion/extension. Ruby Behaviors[2] has the same
principle, though it's more proof-of-concept.


David

[1]
http://blade.nagaokaut.ac.jp/~sinara/ruby/import-module/import-module-0.82/
[2] http://raa.ruby-lang.org/project/ruby_behaviors/

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