fn_box

Box up your FnOnces!

API

```rust trait FnBox, args: Args) -> Result; }

impl FnBox for F where F: FnOnce { … }

[cfg(not(whencoherenceis_fixed))]

impl<'a> FnOnce() for Box { … }

[cfg(whencoherenceis_fixed)]

impl<'a, Args, Result> FnOnce for Box + 'a> { … } ```

Usage

```rust let hello: Box

let plusone: Box _> = move |:x: uint| { x + 1 }; asserteq!(plusone.callbox((3,)), 4); ```