From: Vince H&K <vince.hetk@...>
Date: 2007-03-24T21:05:04+09:00
Subject: Re: Question about if in Ruby

Trans wrote:
> There is one other difference.
> 
>   if a = 1
>     p a
>   end
> 
>   p a if a = 1
> 
> The later does not assign the a.

  This is not exactly true (at least on ruby 1.8.6):

irb(main):001:0> if a = 1
irb(main):002:1> p a
irb(main):003:1> end
1
=> nil
irb(main):004:0> p b if b = 2
NameError: undefined local variable or method `b' for main:Object
        from (irb):4
        from :0

  It doesn't create the variable b in the same scope as the one of the
instruction. However:

irb(main):007:0> a = 1
=> 1
irb(main):008:0> p a if a = 2
2
=> nil
irb(main):009:0> a
=> 2

  It does assign it if it already exists in the current scope. Works as
well in ruby (it is not an irb artifact).

  Cheers,

	Vince

-- 
Vincent Fourmond, PhD student (not for long anymore)
http://vincent.fourmond.neuf.fr/