From: Trans <transfire@...>
Date: 2005-11-05T06:57:09+09:00
Subject: Re: Some comments on new 1.9 features


Domenico De Felice wrote:
> Dale Martenson wrote:
> > Sorry for the misunderstanding.
> >
> > I like the "local" and "share" directives. That would make it clear.
> >
> > Using too many special characters clutter the code and worsen
> > readability.
>
> Yes, something like
>
> { |a, b|
>    local a
>    share b
>    a = 1
>    b = 2
> }
>
> would look less weird. However it has the problem that in bigger blocks
> the programmer would need to read back the top of the block when he
> 'forgets' which attributes are local and which shared.

They would'nt *have* to be just at the top. You could even do it
conditionally, although usage is subtle:

  x = false

  a = 1
  b = 2
  lam1 = lambda { |a, b|
     a = 2
     b = 4
     if x
       share b
     end
  }
  lam2 = lambda { b + 1}

  lam1.call
  lam2.call #=> 3

  x = true

  lam1.call
  lam2.call #=> 5

Closure Magic, yes?

T.