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Re: [Scheme-reports] Procedural equivalence: the last debate

Alex Shinn scripsit:

> As I see it, once a procedure escapes, the existence of any semantics
> in the language which can discriminate the procedure location requires
> it to be boxed.  This is true whether the discriminator is eq? or eqv?.

Well, it depends what you mean by "boxed".

It means that the location tag no longer has to be identified with the
unique address of the procedure.  The procedure can be copied any number
of times (each of which is distinguishable by `eq?`), but the location
tag (which is what `eqv?` looks at) has to be copied with it; it can be
any arbitrary value at least as wide as an address.

I suggest you solicit aid of my followers       John Cowan
or learn the difficult art of mud-breathing.    cowan@x
        --Great-Souled Sam                      http://www.ccil.org/~cowan

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