From: Luis Lavena <luislavena@...>
Date: 2008-04-05T02:23:49+09:00
Subject: Re: RUBY_IMPLEMENTATION

On Fri, Apr 4, 2008 at 2:15 PM, Chris Cummer <chris@postal-code.com> wrote:
> On 4-Apr-08, at 3:05 AM, Eleanor McHugh wrote:
>
>
> > Well RUNTIME makes more sense to me than ENGINE, but it still suggests
> that code should be written to suit a particular runtime when what coders
> really want to know is what FEATURES are available on the platform.
> >
> > I therefore favour a constant RUBY_FEATURES
> >
>
>  This is the first time I've seen this particular suggestion put forth and
> at the risk of being heretical, what about both?
>
>  I see merit in Alex's use-case (though I'm not fond of the over-loading of
> "require"; perhaps feature_exists?() instead?):
>
>
> > begin
> >  feature_exists?( Features.threading.native )
> >
> >  setup_code_for_native_threads()
> >  FeatureSet::Threading::Native # => true
> > rescue LoadError
> >  feature_exists?( Features.threading.green ) # or let this be a default
> >
> >  setup_code_for_green_threads()
> >  FeatureSet::Threading::Green # => true
> >  FeatureSet::Threading::Native # => false
> > end
> >
>
>  yet at the same time it feels right to be able to "know" as much as
> possible about the actual environment in which the code is running. Of all
> the proposed suggestions I find RUNTIME to be the most palatable.
>


Mmm, why don't use the current available keywords?

if defined? FeatureSet::Threading::Native
  # ...
else
  # ...
end


Now we are under that road, what about the dread fork() on Windows?

NotImplementedError: fork() function is unimplemented on this machine

fork { ... } if defined? FeatureSet::Process:Fork

-- 
Luis Lavena
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