Bool in Data.List

[mechvel]

Data.List.Base has filter based on Decidable P (which I like),
but span, dropWhile and some others still base on Bool.
This looks strange.

[MatthewDaggitt]

I agree. They should be changed to use predicates as well.

[MatthewDaggitt]

Closed with 80d49dc. As with filter and partition left the boolean versions in to help backwards compatibility for those who are determined not to use the better versions.