You can add a type hint to function arglists to indicate the return type of a function like so.
The problem is that now when I call `linkedlist` exactly as above from another namespace, I'll get an exception because java.util.List is not imported in there.
There are two workarounds: You can import the hinted type also in the calling namespace, or you always use fully qualified class names for return type hints. Clearly, the latter is preferable.
But clearly, that's a bug that should be fixed. It's not in analogy to type hints on function parameters which may be simple-named without having any consequences for callers from other namespaces.
Approach: Make the compiler resolve the return tags when necessary (tag is not a string, primitive tag (^long) or array tag (^longs)) and update the Var's :arglist appropriately.