constraint deduction bug?
Gabor Greif
ggreif at gmail.com
Fri Mar 22 00:59:53 CET 2013
In context of a bigger source file I got this error from GHC (HEAD)
Could not deduce (Intersect
[KeySegment] (BuriedUnder sub k ('Empty
[KeySegment])) inv
~ 'Empty [KeySegment])
from the context (Intersect
[KeySegment] (BuriedUnder sub k ('Empty
[KeySegment])) inv
~ 'Empty [KeySegment])
bound by a pattern with constructor
Nil :: forall (k :: BOX). Sing (Inventory k) ('Empty k),
in a pattern binding in
'do' block
Can somebody confirm that this constraint should be trivially deducible from
the context?
Then I'll try to come up with a reduced repro case.
Cheers,
Gabor
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