From: Eric Mahurin <eric_mahurin@...>
Date: 2005-09-29T00:29:27+09:00
Subject: Re: creating independent lambdas in loops

--- Gavin Kistner <gavin@refinery.com> wrote:

> On Sep 28, 2005, at 7:47 AM, Eric Mahurin wrote:
> >> Completely true. If a variable of that name is already
> >> defined it is
> >> used (and no local variables are created).
> >
> > Does anyone else find this "feature" useful?
> 
> All the time! I would say that at least half the programs I
> write use  
> this feature of the blocks-as-closures.

I'm talking about specifically block arguments (the only
variables in a block that can be local to the block).  i.e.
this:

x = 0
[1,2,3,4].each {|x|}
x # => 4 # block argument changed x

compared to:

[1,2,3,4].each {|x|}
x # undefined local variable or method 'x'

I find this dual behavior annoying - that a local variable is
created only if the variable doesn't exist in the current scope
already.  I would have rather it always be created so that if
you did want an argument to be assigned to a variable outside
the block, you'd have to do it explicitly:

x = 0
[1,2,3,4].each {|y| x = y }
x # => 4




		
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