[ruby-core:33356] Re: [Ruby 1.9-Feature#4085][Open] Refinements and nested methods

Hi,

2010/11/25 Yusuke ENDOH <[e-mail]>:
>> As I said at RubyConf 2010, I'd like to propose a new features called
>> "Refinements."
>
>
> Basically I agree with your proposal, but I think that some
> discussion is needed.
>
>  Your patch is too big. ould you separate it to some parts?
> t is hard (for me) to review it.

Shyouhei suggested github, but my github account has no enough disk
space, so I put the git format-patch result at the following site:

  http://shugo.net/tmp/refinement-r29837-20101124.zip (ZIP archive)
  http://shugo.net/tmp/refinement-r29837-20101124/ (Expanded directory)

However, I'm afraid that there are too many patches, some of which
have been already reverted.

>  Your patch adds `klass' to stack frame, which may cause
> ig performance degradation. e should check benchmark
> esult (though I'm not so concerned).

I have run "make benchmark" 5 times, and it shows that the modified
version is slower than average 2.5% than the original version.

The benchmark result is available at:

  http://shugo.net/tmp/refinement-benchmark-20101107.csv

Additional tests are welcome.

>  API design. hy did you select:
>
> odule MathN
> efine(Fixnum) do
> ef /(other) quo(other) end
> nd
> nd
> sing MathN
>
> nd not select others, such as:
>
> odule MathN
> efine(Fixnum)
> ef /(other) quo(other) end
> nd
> sing MathN
>
> r:
>
> athN = refine(Fixnum) do
> ef /(other) quo(other) end
> nd
> sing MathN

Because I'd like to allow multiple refinements in one module, for
example, in the following case:

  module MyXmlFormat
    refine Integer do
      def to_xml; ...; end
    end

    refine String do
      def to_xml; ...; end
    end

    refine Hash do
      def to_xml; ...; end
    end
    ...
  end

In this case, I prefer the above syntax to your proposals.

> MO, it will be more natural to provide this feature as new
> onstract with new syntax, instead of Module's methods.

First, I consider it, but I wouldn't like to introduce new keywords.

>  Is it intended to reject refining module methods?
>
> odule ComplexExt
> efine(Math) do
> ef sqrt(x)
> x >= 0 ? 1 : Complex::I) * super(x.abs)
> nd
> nd
> nd
> => wrong argument type Module (expected Class) (TypeError)

It's limitation of the current implementation.
However, I don't think it's critical, because If you'd like to refine
a module, you can refine a class which includes the module instead.

-- 
Shugo Maeda