From: Douglas Livingstone <rampant@...>
Date: 2005-06-13T11:35:55+09:00
Subject: Re: Only if the object exists

On 6/12/05, Gavin Kistner <gavin@refinery.com> wrote:

> def foo
>      10.times{ i = i ? i+1 : 1 }
>      puts i = i ? i+1 : 1
>      10.times{ i = i ? i+1 : 1 }
>      puts i = i ? i+1 : 1
> end
> 
> results in "1" and "12" being written, instead of "11" and "22".
> 
> Ruby is the first language I've seen where the scope of a variable is
> not the same throughout the same block. 

{ i = i ? i+1 : 1 } is a new block. Setting i inside this block
doesn't bubble up to the parent unless i is already defined.

Compare with:

def bar
    i = 0
    10.times{ i = i ? i+1 : 1 }
    puts i = i ? i+1 : 1
    10.times{ i = i ? i+1 : 1 }
    puts i = i ? i+1 : 1
end

I'd call it a bug, we'll see if it still happens in Ruby2.

Duglas