Use Anys, not wildcards, for converter output types #139
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gselzer
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| if (t instanceof TypeVariable<?>) { | ||
| TypeVariable<?> tv = (TypeVariable<?>) t; | ||
| return Nil.of(new Any(tv.getBounds())); | ||
| } | ||
| var vars = new HashMap<TypeVariable<?>, Type>(); | ||
| for (Type typeParam : typeParams) { | ||
| if (typeParam instanceof TypeVariable<?>) { | ||
| // Get the type variable | ||
| TypeVariable<?> from = (TypeVariable<?>) typeParam; | ||
| // Create a wildcard type with the type variable bounds |
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This comment is no longer correct.
| @@ -55,7 +55,7 @@ public class IdentityCollection<T, U extends T> implements OpCollection { | |||
| @OpHints(hints = { Conversion.FORBIDDEN, | |||
| BaseOpHints.DependencyMatching.FORBIDDEN }) | |||
| @OpField(names = "engine.convert, engine.identity", priority = Priority.FIRST) | |||
| public final Function<U, T> identity = (t) -> t; | |||
| public final Function<T, T> identity = (t) -> t; | |||
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The parens are unnecessary; you can just write t -> t.
| * Op. | ||
| * </p> | ||
| */ | ||
| @OpMethod(names = "test.boundsConversion", type = BiFunction.class) |
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Once again I got confused by the name of this op. It's weird to me that we have test ops named after the functionality being tested rather than named for what they do like normal ops. In this case, the op test.boundsConversion is a static method named foo (which I find unhelpful in understanding) and it returns the max of two objects. So why not name it "max" instead? Especially since the functionality being tested here, multiple type bounds, is also a sort of comparison, which was the source of my momentary confusion: "What does x > y ? x : y have to do with multiple bounds?" I thought, "It's just one bound..."
Wildcard types are problematic due to the restrictions on e.g. the number of bounds.
Anys are more flexible in this regard, and better reflect our needs.TODO: