From: Hugh Sasse Staff Elec Eng <hgs@...>
Date: 2000-08-07T16:25:37+01:00
Subject: [ruby-talk:04331] Re: TABWTDI and Hash.new([])

Hmm.  that took me a while to figure out!  I think that is good.

	Hugh.
	hgs@dmu.ac.uk

On Mon, 7 Aug 2000, ts wrote:

> >>>>> "H" == Hugh Sasse Staff Elec Eng <hgs@dmu.ac.uk> writes:
> 
> H> I agree with those sentiments as well.  I wonder if this would be worth
> H> extending more gnerally, so user-created classes can use it?
> 
>  Something like this ?
> 
> pigeon% cat b.rb
> #!/usr/bin/ruby
> class A
>    def initialize
>       @a = []
>       @obj = if iterator?
>                 Proc.new
>              else
>                 nil
>              end
>    end
>    def add(*args)
>       @a += if @obj &&  args.size == 0
>                @obj.call
>             else
>                args
>             end
>    end
> end
>  
> a = A.new {[1, 2] + 1}
> a.add
> p a
> a.add [12, 24]
> p a
>  
> pigeon% b.rb
> #<A: @a=[1, 2, 1], @obj=#<Proc:0x401675d0>>
> #<A: @a=[1, 2, 1, [12, 24]], @obj=#<Proc:0x401675d0>>
> pigeon% 
> 
> 
> Guy Decoux
> 
>