Motivation for refineDefaultAlt

Matthew Pickering matthewtpickering at
Fri May 11 14:53:32 UTC 2018

Hi all,

Does anyone know the motivation for refineDefaultAlt?

The comment states

- -- | Refine the default alternative to a 'DataAlt', if there is a unique
way to do so.

OK - so the code transforms something like

case x of { DEFAULT -> e }
case x of { Foo a1 a2 a3 -> e }

but why is this necessary or desirable?

Perhaps you know Simon (Jakobi)?


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