[m-dev.] type classes and the color blue

[Michael Day]

Hi,

Does the following code make any sense at all:

:- typeclass thing(T) where
	[
		pred is_blue,
		mode is_blue is semidet
	].

:- instance thing(sky) where
	[
		pred(is_blue/1) is semidet_succeed
	].

:- instance thing(sun) where
	[
		pred(is_blue/1) is semidet_fail
	].

...

:- pred both_blue(A, B) <= (thing(A), thing(B)).
:- mode both_blue(in, in) is semidet.

both_blue(A, B) :- ... what can go here? ...

Is there a way to qualify methods by variable name?

Michael

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