Re: [ ruby-Bugs-7680 ] a block argument within a block which argument has the same name leaks

On Jan 8, 2007, at 7:06 PM, Yukihiro Matsumoto wrote:

> Hi,
>
> In message "Re: [ ruby-Bugs-7680 ] a block argument within a block  
> which argument has the same name leaks"
>     on Tue, 9 Jan 2007 11:57:56 +0900, [e-mail] writes:
>
> |It's an interesting case, and I can definitely see that it  
> wouldn't be
> |easy to implement.  What about just not having the warning?  Mostly
> |people wanted block-locals so that they could stop worrying about the
> |names.  So maybe it isn't necessary for the compiler to warn.
>
> Using in-block variable outside is the biggest source of my mistakes
> in Ruby.  I'd like to address this issue in the future.  Until then,
> it will warn to reduce my headache.

I agree they need work. Why not go back to the rubyconf 2005  
proposal? I believe it was to allow new vars created in a block to be  
normal local variables (not dvars). I've discussed the expected  
behavior of local variables in ruby to new users and this is what  
they expect. The other expected behavior is that block arguments are  
seen to all code 'below' the block and not to any code above.. For  
example:

a = [1,2]
a.each do |i|
   m = "hello"
   i.upto(10) do |j|
     n = "evan"
     # i, j, n, m are seen here.
   end

   # j is NOT seen here.
   # i, m and n are seen here.
end

# i and j are not NOT seen here.
# m and n are seen here.

Thoughts?

>
> 							matz.
>