Isn't deleteBy achievable via a filter?

It would be more ineffecient if I had to convert my lists to Data.Sets ot Data.Maps every time... For small lists, the operations are simple and practical. This doesn't have anything with generalization of type signatures anyway.

2018년 11월 1일 (목) 11:58에 David Feuer <david.feuer@gmail.com>님이 작성:

I don't think it's really so great that Data.List has a bunch of operations that are inefficient on lists.

On Wed, Oct 31, 2018, 10:53 PM Dannyu NDos <ndospark320@gmail.com wrote:

I've suffered from inconvenience due to the restricted type signature. I'll be very glad if such restrictions are lifted:

deleteBy :: (a -> b -> Bool) -> a -> [b] -> [b]

deleteFirstsBy :: (a -> b -> Bool) -> [a] -> [b] -> [b]

intersectBy :: (a -> b -> Bool) -> [a] -> [b] -> [a]

I approve these versions because:

1. It makes more sense that the "usual" `delete` and `intersect` functions are specialization of the "By" operations, not the vice versa.

2. Data.Map.Lazy module from containers package has these kind of "By" operations.

The previous discussion about this in Sep 2016 didn't make much conclusion, so let the discussion continue.

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