proposal: add 'unsafeCoerce'

[Ross Paterson]

On Mon, Nov 20, 2006 at 04:51:29PM +1100, Donald Bruce Stewart wrote:
> So the uses fall into 2 categories:
> 
>   * FFI binding and raw pointer/foreign data manipulation
>   * type equalities known, but not expressible statically
> 
> Now, can we say something portable about these uses?

The second group, perhaps, but the first group (unsafeCoerce#) depend
on GHC's internal representations.