allow recursive object methods

[erickt]

It's a bit obnoxious when writing an object type that can return instances of itself that we need a tag to break up the recursion:

tag foo_tag = foo;

type foo = obj {
    fn get_children() -> [foo_tag];
};

obj new_foo() {
  fn get_children() -> [foo_tag] { [] }
}

It'd be much nicer if rust would just let us write fn get_children() -> [foo].

[nikomatsakis]

this is a particular instance of the fact that rust doesn't support recursive structural types (it's not really specific to objects). replacing objects with pcwalton-style classes/interfaces (which are nominally typed) would address this problem.

[marijnh]

No longer an issue on ifaces. Closing.