[Haskell-beginners] Bool newtype

Imants Cekusins imantc at gmail.com
Sun Aug 7 21:12:26 UTC 2016

Thank you Theodore.

> Data.Coerce

Could you hint the name of the package, please? Does it coerce safely?

If Coercible does not type check, another option could be to define a class
and a function that works similar to if statement, constrained to instances
of this class.

class Newtype_base nt base where
  base_t::nt -> base

if_::Newtype_base nt Bool =>
   nt -> then -> else

Standard if is clearer of course but with a few newtypes being passed
around, this may save some key strokes.
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