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Estimated hours taken: 0.25 tests/hard_coded/nullary_ho_func.m: tests/hard_coded/nullary_ho_func.exp: Test the output of type_name/1 for nullary higher-order function types.
50 lines
1.3 KiB
Mathematica
50 lines
1.3 KiB
Mathematica
% Test case for use of zero-arity higher-order function terms.
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%
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% Author: fjh
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:- module nullary_ho_func.
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:- interface.
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:- import_module io.
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:- pred main(io__state::di, io__state::uo) is det.
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:- implementation.
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:- import_module std_util.
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:- type nullary_func(T) == ((func) = T).
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:- inst nullary_func == ((func) = out is det).
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:- func apply_nullary_func(nullary_func(T)) = T.
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:- mode apply_nullary_func(in(nullary_func)) = out is det.
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apply_nullary_func(F) = apply(F).
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:- func apply_func((func) = T) = T.
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:- mode apply_func((func) = out is semidet) = out is semidet.
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:- mode apply_func((func) = out is det) = out is det.
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apply_func(F) = apply(F).
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main -->
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{ F = ((func) = 42) },
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{ X = apply(F) },
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{ G = ((func) = (_ :: out) is semidet :- fail) },
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{ H = ((func) = (R :: out) is semidet :- semidet_succeed, R = X) },
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print("X = "), print(X), nl,
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print("apply(F) = "), print(X), nl,
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print("apply_func(F) = "), print(X), nl,
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print("apply_nullary_func(F) = "), print(X), nl,
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( { Y = apply(G) } ->
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print("Y = "), print(Y), nl
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;
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print("Y = apply(G) failed"), nl
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),
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( { Z = apply(H) } ->
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print("Z = "), print(Z), nl
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;
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print("Y = apply(G) failed"), nl
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),
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print("type_of(F) = "), print(type_of(F)), nl,
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print("type_name(type_of(F)) = "), print(type_name(type_of(F))), nl.
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