SWI currently provides partial support for rational numbers. From the reference manual ( 4.27.2.1 Arithmetic types): “In the long term, it is likely that rational numbers will become atomic as well as a subtype of number. User code that creates or inspects the rdiv(M,N) terms will not be portable to…

I think all of that makes sense. Ruby style 3/2R would be acceptable syntax to me. 3/2r is a little dodgy, although 0b1101 is also valid (ISO) Prolog syntax while it is ambiguous if b is defined as an infix operator. I don’t know how much will break if X is 1/2 no longer produces a float. The no…

I think all of that makes sense. Ruby style 3/2R would be acceptable syntax to me. 3/2r is a little dodgy, although 0b1101 is also valid (ISO) Prolog syntax while it is ambiguous if b is defined as an infix operator. As is 1e1 if e is defined as an infix operator. So I think there’s a va…

[image] ridgeworks: 2==2.0 As you probably know, there is term equivalence (==) and numerical equivalence (=:=), where the latter implies synchronizing the types and comparing according to the logic for that type. Not much changes to that when adding rational numbers. [image] ridgeworks: …

I see no errors or even strange things.

I guess JanB is just not happy with the type coercion. This is obviously not a “bug” by any definition of the word, it is a design choice. PS: One of the small annoyances when switching between languages on a regular basis is that the meaning of arithmetic operators subtly differs. I find myself of…

[image] Boris: I guess JanB is just not happy with the type coercion He is not clear about that. The rules are a bit dubious because as long as rationals are not proper numbers we cannot support them easily in normal / division and needed the rdiv construct. Other than that, basically ari…

[image] anon95304481: Should give the same result. Its the same computation. Yes, but as @ridgeworks correctly claims, rationals are currently too awkward to use them as the default result for 1/3, i.e. ?- X is 1 rdiv 3, number(X). false. That may be acceptable as a kludge allowing for s…

2==2.0 As you probably know, there is term equivalence (==) and numerical equivalence (=:=), where the latter implies synchronizing the types and comparing according to the logic for that type. Not much changes to that when adding rational numbers. Except that [1/2r, 1, 1.25, 3/2r] would be unch…

Future of support for rational numbers

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Future of support for rational numbers

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