[m-rev.] for review: uint operations in array.m

[Zoltan Somogyi]

On Sat, 3 Jan 2026 02:02:21 +1100, Julien Fischer <jfischer at opturion.com> wrote:
> You will need to be particularly careful with this. Our target
> languages impose a number of constraints on arrays.
> The main two that are relevant here are that
> 
> 1. In C# and Java, array index expressions have type int; indexes
>    of other integral types will be implicitly converted (where allowed).

I left the predicates implemented using foreign_procs using ints. None
have been changed to use uints.

> Obviously, some operations, such as size/1 will always be safe. I've noted
> one group below that definitely are not in their present form and I think
> correctness arguments need to be made for some of the others.

Which others?

> > +uinit(Size, Item, Array) :-
> > +    array.init_2(uint.cast_to_int(Size), Item, Array).
> 
> As I mentioned above, this will be a problem. Consider, the following on a
> system where int and uint are 32-bit:
> 
>    array.uinit(2147483648u, "foo", Array)
> 
> Ditto for all of the predicates and functions that create an array from a given
> size in some way (e.g. generate and friends).

Thanks for catching that. The attached interdiff covers those predicates.

Do you have comments on the rest of the diff?

Zoltan.



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