From: dblack@...
Date: 2006-10-10T17:52:48+09:00
Subject: Re: [ruby-cvs:18323] ruby: * eval.c (splat_value): use "to_splat" instead of "to_ary" to

Hi --

On Tue, 10 Oct 2006, Yukihiro Matsumoto wrote:

> I wrote:
>
> |The possible problem with to_values is that it suggests that what was
> |there before the conversion was *not* values, which I think might be
> |misleading.  to_args still seems too specific to me -- for example, in
> |this:
> |
> |   [*0...10]
> |
> |there's nothing arg-related about what's happening to the range.
>
> It was *a value* before conversion.

I see what you mean.

> |I also have a question about the use of this method.  Do you think it
> |would always be defined in terms of the * itself?  In other words:
> |
> |   class C
> |     def initialize(a)
> |       @array = a
> |     end
> |     def to_values
> |       *a
> |     end
> |   end
> |
> |But then wouldn't it just return an array?  Or would the * still
> |un-array it?
> |
> |   c = C.new([1,2,3,4])
> |   Hash[*c]             # == Hash[1,2,3,4] ?
> |
> |But then... why have a separate definition?  I'm sure there's a reason
> |-- I'm just not yet seeing how one would use it.
>
> I am not sure I understand you here.  Here's little bit modified your
> example.
>
>   class C
>     def initialize(a)
>       @array = a
>     end
>     def to_values
>       @array
>     end
>   end
>
>   c = C.new([1,2,3,4])
>   Hash[*c]             # == Hash[1,2,3,4]
>
> Do you see any problem?

No, I think I got myself twisted around an extra * :-)


David

-- 
                   David A. Black | dblack@wobblini.net
Author of "Ruby for Rails"   [1] | Ruby/Rails training & consultancy [3]
DABlog (DAB's Weblog)        [2] | Co-director, Ruby Central, Inc.   [4]
[1] http://www.manning.com/black | [3] http://www.rubypowerandlight.com
[2] http://dablog.rubypal.com    | [4] http://www.rubycentral.org