Newtype wrappers

Johan Tibell johan.tibell at
Tue Jan 15 00:11:25 CET 2013

On Mon, Jan 14, 2013 at 2:57 PM, Roman Cheplyaka <roma at> wrote:
> It's described here:

We seem to be talking past each other. There's a specific problem
related to type classes and invariants on data types mentioned earlier
on this thread. Simon's solution here seems to be that we only coerce
a structure from one newtype to the base type if the constructors are
exposed, hence my question if the code changes semantics due to adding

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