From: Pit Capitain <pit@...>
Date: 2005-07-20T05:00:43+09:00
Subject: Re: [RCR] nil for unassigned keys

Hi Daniel.

> Then what about this?
> 
>    def baz(a, b=nil, c) ... end
> 
> Isn't that just as easy to grasp as this?
> 
>    def baz(a, *b, c) ... end

Yes it is. It was the following definition, which was confusing to mee:

    def bar(a, b=nil, c, d=nil, e) ... end

> I think restricting this to “only if
> there's a splat argument somewhere!” is pretty arbitrary.
> 
> If you wanted the semantics of this,
> 
>    def baz(a, b=nil, c) ... end
> 
> you'd have to write it like this,
> 
>    def baz(a, *dummy, b=nil, c)
>      dummy.empty? or raise ArgumentError
>      ... end
> 
> which seems pretty annoying-for-no-reason.

I was thinking of just adding some mandatory parameters after the 
parameter lists that are allowed today (of course before a block 
parameter). So the following would be allowed:

   def baz(a, b=nil, c)
   def baz(a, *b, c, d)
   def baz(a, b=nil, *c, d, e)

but not the following:

   def baz(a, *b, c=nil)
   def baz(a, b=nil, c, d=nil, e)

Of course, this is only my personal opinion. If you can think of other 
use cases where you'd like to have even more flexibility, please go 
ahead. In any case I'm looking forward to the RCR.

Regards,
Pit