From: Florian Gross <flgr@...>
Date: 2004-05-26T05:43:50+09:00
Subject: Re: ruby-dev summary 23459-23562

Mark Hubbart wrote:

>> 1) What will yield(*[]) do?
> I would assume the same as currently: it expands to zero arguments, 
> becomes yield()

Yes, but does this translate to an empty Values object? What happens 
when it is used in assignment or block parameters?

> Why would rescoping rules be changed? Currently, when you call 
> define_method, Class.new, Module.new, etc., the block is rescoped (is 
> that the right word?) and local variables never leak in. So, assuming 
> they don't make a silly change, define_method would be _exactly_ 
> orthogonal to def...end:

Currently those constructs aren't identical and that allows us to do 
some very interesting stuff. IMHO that behaviour is also a good thing 
because it makes blocks very consistent. You also have access to 
variables of surrounding scopes in .instance_eval, for example. Here's 
an useless, but interesting example -- there are also cases where this 
is useful, however.

   class Foo
     count = 0
     define_method(:initialize) do
       count += 1
       @number = count
     end
     attr_accessor :number
   end

   (1..10).map { Foo.new.number } # => [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]

> Disclaimer: This is only based on the way I read it; I could very likely 
> be all wet. :)

I don't know -- as always, it would be very interesting to know matz' 
opinion about all this. :)

> cheers,
> Mark

Regards,
Florian Gross