From: Tom Jordan <tdjordan@...>
Date: 2006-08-16T06:25:42+09:00
Subject: Re: block equality

ruby version:

ruby 1.8.4 (2006-04-14) [i386-mswin32]

On 8/15/06, Tom Jordan <tdjordan@gmail.com> wrote:
> Is there a way to compare two blocks with each other?
>
> If you promote a block into a Proc, how would you know that the
> original block was the same?
>
> This is what I want to do
>
> (1..10).each do
>   once { puts "Hi Tom"}
> end
>
> I've tried to implement once like this
>
> class << self
>         def once(&block)
>                 @ids ||= {}
>                 block.call unless @ids.key? block.object_id
>                 @ids[block.object_id] = :true
>                 puts @ids.keys.join(', ')
>         end
> end
>
> I've even tried a varient using == and ===
>
> def l(&b)
>   @t ||= b
>   puts b == @t
>   puts b === @t
>   @t = b
> end
>
> (1..2).each { l{x=1} }
>
> output:
> true
> true
> false
> false
>
> How can you compare two procs that have the same body?
>
> Thanks,
> -- Tom.
>
> --
> "Nothing will ever be attempted, if all
>  possible objections must first be
>  overcome." - Samuel Johnson
>
> "Luck is what happens when
>  preparation meets opportunity." - Seneca
>


-- 
"Nothing will ever be attempted, if all
 possible objections must first be
 overcome." - Samuel Johnson

"Luck is what happens when
 preparation meets opportunity." - Seneca