Fix #3443: adapt child compatibility check #3446
Merged
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Fix #3443
Previously, the child compatibility check will result in a check like
CNil <: TVar(Nothing..Coproduct)
, which failed. Now we expose type param according to its variance. We only resort toTVar
if the variance is 0.This PR also removes the
@unchecked
check, as agreed with @allanrenucci the check should be somewhere else and handle more complex cases.