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e4fba268ec
Estimated hours taken: 1/4 Fix test case... the compiler was getting tripped up by a different bug than the one this was meant to be testing. ts/valid/instance_superclass.m: Fixed so it doesn't have an unbound type variable. (Actually, I don't really see why the compiler thinks it is unbound).
31 lines
728 B
Mathematica
31 lines
728 B
Mathematica
:- module instance_superclass.
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% This is a regression test for the case where there is a superclass
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% relationship, and the instance declaration has a type variable in the
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% instance type.
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:- interface.
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:- import_module list.
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:- typeclass c1(T) where [ ].
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:- typeclass c2(T) <= c1(T) where [ ].
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:- instance c1(list(T)) where [ ].
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:- instance c2(list(T)) where [ ].
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:- pred p(T::in) is det.
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:- implementation.
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% The bug that this test case is checking for is at the creation of
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% the typeclass info for this call: if the substitution from "T" in
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% the typeclass decl to "list(T)" in the instance is applied
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% recursively, an infinite loop results.
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p(X) :- q([X]).
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:- pred q(T) <= c2(T).
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:- mode q(in) is det.
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q(_).
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