From: Charles Oliver Nutter <charles.nutter@...>
Date: 2007-07-13T16:33:30+09:00
Subject: Re: Proposal: runtime-modifying Kernel methods should be keywords

John Lam wrote:
>> 3. These methods are exactly the ones that complicate optimizing Ruby in
>> all implementations, including Ruby 1.9, Rubinius, JRuby, Ruby.NET, and
>> others. They confound a compiler's efforts to optimize calls by always
>> leaving open questions about the behavior of a method. Will it need
>> access to a heap-allocated scope? Will it save off a binding or the
>> current call frame? No way to know for sure, since they're methods.
> 
> +1
> 
> We have a design (not implemented yet) to throw on an attempt to alias
> Kernel#eval by default. We would enable aliasing eval with a command
> line switch along the lines of /MakeItRunSlower :) We have a number of
> optimizations for non-local control flow that take advantage of using
> static analysis of a block/proc body. These optimizations simply
> cannot work in cases where eval appears within the block/proc. If
> folks could alias eval then we can't do any of the optimizations at
> all, and that is clearly a bad thing.

I'm thinking about and have partially implemented an almost identical 
design for JRuby for this and a few other methods.

I think it's also worth stating again that this isn't just for 
optimization purposes (though that's big)...it's because these features 
really aren't methods and I feel like they shouldn't masquerade as such.

- Charlie