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mi

There are two examples in this folder. The first one is an adoption of a multi-inheritance C++ example found on the D. M. Capper book "Introducing C++ for Scientists, Engineers and Mathematicians" published by Springer-Verlag. It uses dynamic predicates for storing state. The second example is a variant of the first one using parametric objects.

This example defines the following objects:

[120, 121, 122]

this object space stores spatial coordinates using a dynamic predicate

[116]

this object stores a time stamp using a dynamic predicate

[120, 121, 122, 116]

this object inherits from both the objects xyz and t

[120, 121, 122, 40, 95, 44, 95, 44, 95, 41]

similar to object space but using parameters instead of dynamic predicates

[116, 40, 95, 41]

similar to object space but using a parameter instead of a dynamic predicate

[120, 121, 122, 116, 40, 95, 44, 95, 44, 95, 44, 95, 41]

this object inherits from both the objects xyz(_,_,_) and t(_)

Print Logtalk, Prolog backend, and kernel versions (if running as a notebook):

%versions

Start by loading the example:

logtalk_load(mi(loader)).

Set a point in the space-time:

xyzt::rotate(1, 2, 3).

<!-- true. -->

xyzt::translate(4).

<!-- true. -->

Verify it:

xyzt::xyzt(X, Y, Z, T).

<!-- T = 4, X = 1, Y = 2, Z = 3. -->

Enumerate xyzt public predicates:

%%table
xyzt::current_predicate(Functor/Arity), functor(Pred, Functor, Arity), xyzt::predicate_property(Pred, declared_in(Object)).

<!-- Pred = xyzt(_A,_B,_C,_D), Arity = 4, Object = space_time, Functor = xyzt ? ; Pred = xyz(_A,_B,_C), Arity = 3, Object = xyz, Functor = xyz ? ; Pred = rotate(_A,_B,_C), Arity = 3, Object = xyz, Functor = rotate ? ; Pred = t(_A), Arity = 1, Object = t, Functor = t ? ; Pred = translate(_A), Arity = 1, Object = t, Functor = translate ? ; false. -->

Query the origin distance from a point in the space-time(_, _, _, _):

xyzt(2,3,4,7)::distance(D).

<!-- D = 5.385164807134504. -->

Query the time:

xyzt(2,3,4,7)::time(T).

<!-- T = 7. -->

Enumerate xyzt(_, _, _, _) public predicates:

%%table
xyzt(2,3,4,7)::current_predicate(Functor/Arity), functor(Pred, Functor, Arity), xyzt(2,3,4,7)::predicate_property(Pred, declared_in(Object)).

<!-- Pred = distance(_A), Arity = 1, Object = xyz(_B,_C,_D), Functor = distance ? ; Pred = time(_A), Arity = 1, Object = t(_B), Functor = time ? ; false. -->