rust-lang/rust — pull request #19514 by jbranchaud (2014-12-04 04:16:54+00:00)
Title: Add initial attempt at implementing BitOr for BTreeSet.

I am trying to add an implementation of `bitor` for `BTreeSet`. I think I am most of the way there, but I am going to need some guidance to take it all the way.

When I run `make check`, I get:

```
error: cannot move out of dereference of `&`-pointer
self.union(_rhs).map(|&i| i).collect::>()
^~
```

I'd appreciate any nudges in the right direction. If I can figure this one out, I am sure I will be able to implement `bitand`, `bitxor`, and `sub` as well.

/cc @Gankro