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Re: Vectors as functions

From: "James McCartney" <asynth@io.com>

> On Friday, August 15, 2003, at 12:29 PM, Joe Marshall 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.
> Are programming language features only valuable that can be optimized?
> For some problems optimization might not be as important as 
> expressivity..

It depends.  Sometimes I want to curtail expressivity because I need to
be able to reason about the code. 

> > If you went a tad further and allowed *syntactic* binding in
> > first-class environments, you'd be truly hosed.
> I understand what is meant by dynamic and static binding. Or compile 
> time or runtime lookup resolution. But what do you mean by "syntactic"?

First-class `macros' that you can re-define on the fly.