From: Hal Fulton <hal9000@...>
Date: 2003-11-29T04:21:21+09:00
Subject: Re: Controlled block variables

T. Onoma wrote:
> On Friday 28 November 2003 12:08 pm, Gavin Sinclair wrote:
> 
>>We can forget about methods, etc.  What we're talking about comes down
>>to this: should this syntax work?
>>
>>   p = proc { |x| x + 1 }
>>   n = p(5)                     # => 6
>>
>>That has been discussed on the list before.  I'm not au fait with all
>>the whys and wherefores, but the proposition has never excited me, nor
>>has it gathered significant support.
> 
> 
> Sure, I understand. I'm just wonder if it can be done. Hence my original 
> question. Or whether there is some impossible barrier. That's all.

One thing that comes to my mind is this:

The () notation seems to make sense for a variable that happens
to refer to a proc. But what if you stick parens on a variable
that isn't a proc? This seems like a syntax error, but it would
have to be detected at runtime.

   foo = proc {...}
   1.upto(5) do |i|
     foo = "Haha!!" if i==4
     foo()   # What happens when i is 4?
   end

Hal