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Re: first-class names
> > What do you mean by "all the costs"? And what do you mean by
> > "canonical implementation"?
> > Cheers =8-} Mike Friede
> >From earlier: "Joe Marshall" <firstname.lastname@example.org> wrote:
> The biggest problem with first-class environments ala MIT Scheme
> is the introduction of new bindings at runtime. If you introduce a
> new binding, the `lexical address' (frame and offset) of a variable
> cannot be statically determined and you have to do a deep search
> every time. It absolutely destroys any sort of compiler optimization.
> So I think the exact question is, if bundling a symbol and its
> environment bypasses the need for a deep search every time, does this
> allow the introduction of new bindings at runtime and also some or all
> of the optimizations possible with ordinary lexical scoping? I
> suppose for a new binding with a supplied destination environment the
> frame is statically known but the offset is not (necessarily) known.
This sounds like dynamic scoping. You can get very fast lookup, but
it has its own problems.