use ;
/// We don't know the size of NSString, so we can only hold pointers to it.
///
/// TODO: Use [`extern type`][rfc-1861] when that gets stabilized.
///
/// [rfc-1861]: https://rust-lang.github.io/rfcs/1861-extern-types.html
/// Implement `RefEncode` for pointers and references to the string.
unsafe