Newtype wrappers

Roman Cheplyaka roma at
Mon Jan 14 23:33:18 CET 2013

* Johan Tibell <johan.tibell at> [2013-01-14 14:29:57-0800]
> Let me rephrase: how will Simon's proposed "data constructors are in
> scope" mechanism work? For example, will
>     let xs :: Map = ...
>     in map MyNewtype xs
> behave differently if the constructors of Map are in scope or not?

Coercion is never implicit. In Simon's original proposal, for example,
you need to define coercion functions using a special syntax.

So this code will always work in the same, traditional way.


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