From: "Florian Groß" <florgro@...>
Date: 2005-09-11T01:36:26+09:00
Subject: Re: quick print type debugging

Eric Mahurin wrote:

> I just took a peek at your code.  This could be quite slow
> because it uses Binding#of_caller (searches stack, uses
> continuations) and eval.  I don't particularly like the idea of
> putting code in a string (editors treat it like a string rather
> than code).  Oh, and  having this debug/trace method return the
> expression value would be very useful.

Why do you think that this is too slow? It's something that only happens 
when debugging. Putting the string into a block doesn't help at all 
because strings are generated at parse-time so you avoid no overhead at all.

True, getting the caller's binding isn't exactly fast, but it only 
happens when debugging. I think you are overrating this as you can make 
trace() a noop when $DEBUG is false. (Just like I do with assert { } in 
ruby-breakpoint.)

I'm pretty sure that Proc#source is way slower than the 
Binding.of_caller solution, by the way.