do not count calls to $reify_switch as inferences
:- use_module(library(control), [(\=)/2]).
:- use_module(library(dif)).
-/* in essence, '$reify_switch'(T, Then_0, Else_0) is this:
+/* in essence, '$reify_switch'(T, Then_0, Else_0) is semantically this:
( T == true -> call(Then_0)
; T == false -> call(Else_0)
; nonvar(T) -> throw(error(type_error(boolean, T), _))
; throw(error(instantiation_error, _))
).
- but without creating choice points.
+ but it does not create choice points.
*/
if_(If_1, Then_0, Else_0) :-
call(If_1, T),
- '$reify_switch'(T, Then_0, Else_0).
+ '$call_with_default_policy'('$reify_switch'(T, Then_0, Else_0)).
=(X, Y, T) :-
( X == Y -> T = true
