Hi --
>> Nobuyoshi Nakada wrote:
>> > Hi,
>> >
>> > At Tue, 24 Jul 2007 17:40:57 +0900,
>> > Marcin Tyman wrote in [ruby-talk:261483]:
>> >> Is any way to define static variables over function? As class static
>> >> variables there is possible to define a static class variable as
>> >> @@name_of_var. But I'm not sure if Ruby let define such variables in
>> >> functions (like in C/C++)
>> >
>> > def foo(x)
>> > (0..0).instance_eval{x,@x = @x,x}
>> > x
>> > end
>> > 3.times{|i|p foo(i)} #=> nil, 1, 2
>> >
>> > The literal object can be Float, Regexp or Bignum, but Range
>> > would be faster a bit.
>> >
>>
>> Interesting. That is because Float, Regexp, and Bignum are instantiated
>> per scope, right?
>>
>> Sometimes a little abstraction leakage can be useful!
>>
>> --
>> vjoel : Joel VanderWerf : path berkeley edu : 510 665 3407
>>
> I did not believe this,and why should I?
> But it seems to be true
> def foo(x)
> (0..0).instance_eval{x,@x = @x,x}
> x
> end
>
> 3.times{ |i| puts foo(i) }
> (0..0).instance_eval{@x=42}
> 3.times{ |i| puts foo(i) }
>
> Run this for a pleasant surpriseI get the same result with or without the line between the two times
calls. Are you seeing it output 42?
No that is the pleasant surprise 
If I understood the Guru Sans correctly that is because the
interpreter defines (0..0) scope locally -- the same object_id
notwithstanding -- amazing feature indeed.
Needless to say that one should rather not use it 
Cheers
Robert
···
On 7/25/07, dblack@wobblini.net <dblack@wobblini.net> wrote:
On Wed, 25 Jul 2007, Robert Dober wrote:
> On 7/24/07, Joel VanderWerf <vjoel@path.berkeley.edu> wrote:David
--
* Books:
RAILS ROUTING (new! http://www.awprofessional.com/title/0321509242\)
RUBY FOR RAILS (http://www.manning.com/black\)
* Ruby/Rails training
& consulting: Ruby Power and Light, LLC (http://www.rubypal.com)
--
I always knew that one day Smalltalk would replace Java.
I just didn't know it would be called Ruby
-- Kent Beck
