[ruby-talk:04340] Re: TABWTDI and Hash.new([])

On Tue, 8 Aug 2000, ts wrote:

> >>>>> "H" == Hugh Sasse Staff Elec Eng <[e-mail]> writes:
> 
> H> So when you wrote that function before, you had already expanded it in
> H> your head beforehand, so the short form never made it into the file. 
> H> Is that what you mean here?
> 
>  yes :-)

OK.
> 
> H> I have not delved into the source yet, so I don't see how this piece fits
> H> into the discussion here :-)
> 
>  When you write :
> 
>        def x(a, b = [], *rest, &block)
>        end
> 
>  ruby will create 2 nodes :
>  
>    * a node NODE_ARGS for (a, b = [], *rest)
>    * a node NODE_BLOCK_ARG for &block
> 
>  the NODE_BLOCK_ARG make something equivalent to :
> 
>     block = nil
>     if iterator?
>        block = Proc.new
>     end
> 

I see where this fits in now. Thank you.  I had forgotten that any 
function can take a block, and when I had remembered this in the
past I had only remmebered about using it with yield.  If iniitialize
were to use yield, then one would not get a new call to the block
when a previously undefined object is created, so this use of the
Proc.new is more flexible.
> 
> Guy Decoux
> 
	Hugh