🚀 go-pugleaf

In article <ROCKWELL.92Apr15002308@socrates.umd.edu> rockwell@socrates.umd.edu (Raul Deluth Miller-Rockwell) writes:
|Jim Giles:

Nope; I said this:

|   ||> [... reduction on empty array ...]
|   ||> Nono, you missed the point. Some operations (like "+") make
|   ||> SENSE for empty arrays, and there you supply the appropriate
|   ||> value (0). Others (like "min") only make sense on an empty
|   ||> array in an extended domain (for present purposes: don't make
|   ||> sense) and so you REQUIRE at least one element, ...
|
|I've been hoping some one else would bring this up, but:  what kind of
|implementation is this, where you've got a numeric type but no maximum
|element of that type?  I wasn't aware that could happen with a finite
|set of numbers -- at least, not for the case where those numbers are
|members of the set of real numbers.

That's not the point. The point is that if I say min({}) and you say
-32768, you are WRONG. That is NOT the answer. min({} union {x}) may
be x, but you've answered based on the extension rather than the
intension and that's a bug in *my* book. And if you say -infinity you
are only right if the type system includes a -infinity point, which it
probably doesn't. Many operations don't even HAVE a consistent
identity, even a notional one like infinity.
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stephen p spackman         Center for Information and Language Studies
stephen@estragon.uchicago.edu                    University of Chicago
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