From: Tom Jordan <tdjordan@...>
Date: 2006-08-17T00:21:39+09:00
Subject: Re: block equality

On 8/15/06, Justin Collins <collinsj@seattleu.edu> wrote:
>
>
> Marshall T. Vandegrift wrote:
> > "Tom Jordan" <tdjordan@gmail.com> writes:
> >
> >
> >> 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?
> >>
> >
> > I haven't dived into the code, but I'm pretty sure that (a) promoting
> > a block to a Proc via &block in the argument list results in a new
> > Proc each time and (b) ruby 1.8 provides no introspection into the
> > actual contents of a block.
> >
> >
> <snip>
>
> Yes, it's kind of like asking if two equations or two methods are equal.
> On the other hand, you could probably use the SerializeableProc
> (developed here: http://rubyquiz.com/quiz38.html), add an equality
> method, and then you'd have it. :)

Thanks Marshall and Justin.

This http://ruby-doc.org/core/classes/Proc.html#M001161

"Return true if prc is the same object as other_proc, or if they are
both procs with the same body."

led me to believe that Procs would evaluate to equality if they had
the same body.

So I would have expected that the following:

s = lambda { x = 1 }
t = lambda { x = 1 }
s == t   # => true expected, false in reality

So my question is; when would the body of Procs ever be the same?

Thanks,
-- Tom.


-- 
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