From: ES <ruby-ml@...>
Date: 2005-10-17T08:32:33+09:00
Subject: Re: Anonymous methods, blocks etc. (Cont. 'default block params')

Wilson Bilkovich wrote:
> I agree. It seems to me that once Ruby has 'real deal' anonymous
> methods, then that's a primitive that could be used to implement the
> other constructs, like Proc.

The hurdle for this, I assume (apart from having to rewrite a lot of
code and another important thing addressed below), is that the closure
feature does not play nice with the current semantics:

   # Pseudosyntax to clarify
   class Foo
     @quux = 42

     def :foo {|x, y, z|
       do_something_with x, y, z
     }

     def :do_something {...}
   end

The closure would grab the environment; @quux would be available and
the implicit 'self' would refer to the Class object, not the instance.
This means that all messages to a given object would invoke some sort
of an #instance_eval on the method's code.

(Please correct me and voice other *technical* issues if any!)

These are by no means unsurmountable but there is quite a bit of work
involved in rewriting.

One big thing, though: one may wish to intentionally make a distinction
between a 'behaviour' of an object and a 'function' which these anons
(and to an extent Procs) can be seen as. I have made my peace by just
thinking of this as a different way of defining those behaviours (it is
not like they actually spawn to life by themselves now) but I can, sort
of, see how the thought might seem unappealing.

> Also, I've been trying not to comment on the arrow thing, but my
> biggest complaint is this:
> In functional notation, an 'f arrow x' means apply the f function to
> the x argument.   The example Ruby syntax is reversing that, and using
> the arrow for specifying a function, rather than using it.
> 
> --Wilson.
> 
> On 10/16/05, robertj <robert_kuzelj@yahoo.com> wrote:
> 
>>hi,
>>
>>are there any non obvious issue why blocks, anonymous methods and
>>methods could or should not be unified?
>>
>>i find it very ugly that i have to call a proc like this
>>aproc.call or aproc[] instead of aproc(). unification of all those
>>constructs would be really great.
>>
>>btw will be possible to get a handle on a instance method in ruby
>>1.9/2.0
>>
>>something like this:
>>aproc = &anInstance.method
>>
>>and then of course
>>aproc()
>>
>>ciao robertj

E