Re: Ranges and (non)static constraints

Robert A Duff wrote:

OK. I'm sure I will enjoy reading the RM for it someday.

As I will yours.

But are you sure you want to define it by what it is NOT,
rather than what it IS? ;-)

I'll define it by what it is, and name it by what it isn't.

String_Index seems reasonable for indexing strings. Machine_Integer
seems reasonable for a type that matches the machine's register size
(but it should not be in Standard). I think one wants a way to say
(e.g.) that a type ranges from 1 up to at least a million, but it's fine
to go beyond that, and please make it efficient (for example, perhaps
round it up to 2**31-1).

Instead of Machine_Integer, perhaps we want a way to define a type that
can count the number of Mumble objects, given that if we create more
than some number of Mumble objects, or an array of them, we can be sure
this count will not overflow. That is, we would have run out of
(virtual) memory before that count overflows.

That would have to be a dynamic type, as the actual upper bound could not generally be known at compile time.

--
Jeff Carter
"Ditto, you provincial putz?"
Blazing Saddles
86
.

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