From: John Lam <jlam@...>
Date: 2007-07-13T16:02:08+09:00
Subject: Re: Proposal: runtime-modifying Kernel methods should be keywords

> 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.

-John