[lmondada]

This adds a map method to Slotmap:

pub fn map<U, F>(&self, mut f: F) -> SlotMap<K, U>
where
        F: FnMut(K, &V) -> U

as discussed in #80.

Closes #80

[lmondada]

If anyone is interested in this: I've created a fork of slotmap with this feature for the time being.

https://crates.io/crates/slotmap_fork_lmondada

Happy to delete it as soon as something like this is merged in and released.

[orlp]

I don't want to merge this because it doesn't take self by value but by reference. I want it to take ownership.

I will add a map that takes ownership.

[lmondada]

Ok, thanks for the response! Let me know if you'd like my help in drafting the new PR.