From: Joao Pedrosa <joaopedrosa@...>
Date: 2007-01-12T02:35:18+09:00
Subject: Re: [ ruby-Bugs-7680 ] a block argument within a block which argument has the same name leaks

Hi,

> |class Scope < Proc
> |end
> |
> |Examples:
> |
> |a)
> |scope {|a,b; v1, v2| ...}
> |
> |b)
> |scope {|v1, v2| n = 10 }
> |p n #error. unknown n
> |
> |c)
> |scope(binding) {|v1, v2| n = 10 }
> |p n #prints 10
> |
> |Then backwards compatibility could be kept.
>
> Unfortunately, local variables scope are determined in compile-time,
> so that run-time feature like scope you've proposed is too late to
> modify local variable behavior.

That's right. I anxiously submitted the email just so I could get the
idea off of my chest. :-) The examples weren't complete, as the code
blocks would need to be run at least once as you hint.

> |That's an idea to try to avoid the "bikeshed talks". hehe. :-)
>
> Unlike FreeBSD people, I _love_ bikeshed talks. ;-)

Just to let you even more at easy, my changes to remove some
"dangerous anonymous functions" actually helped me to clear up
some of my code, because I was able to use the underlying Module
which hosted the anonymous functions as the holder of them, just
as I was doing with a couple of Hashes before. Actually I still use
some anonymous functions now in this same code/library, but they
are a little bit safer as they are very targeted, small, and in a
common library. The bigger and more dangerous functions have
been taken care of for about 8 or so of my libraries. I still need to
make the conversion in two more, though. They all follow the same
standard/framework. :-)

That is, I am not in a hurry anymore and things have been sorted out
in my end. I hope you will be able to sort them in your own now. hehe. :-)
With safer (local scope) anonymous functions, programmability will be even
better soon. I'm looking forward to it. :-)

Cheers,
Joao