Swift 4.1 compactMap for lazy collections

Question

Prior to the Swift 4.1 I used flatMap to remove nil values from collections. Now this method is deprecated and I need to replace it with compactMap. Sometimes I used flatMap with lazy collections to optimise my code, like that:

let optionalIntegers : [Int?] = [1, 2, nil, 3, 4, nil, nil, 5]
optionalIntegers.lazy.flatMap { $0 }.forEach { print("Item \($0 * 10)") }

Will it has the same effect if I will use compactMap instead of flatMap? In documentation for the method lazy I found references to map and filter only.

score 4 · Accepted Answer · answered Apr 19 '18 at 12:18

Yes, absolutely the same. They just decided to remove the ambiguity of flatMap functions and renamed one of them to compactMap not to confuse developers.

Here is the proposal: Introduce Sequence.compactMap(_:)

We propose to deprecate the controversial version of a Sequence.flatMap method and provide the same functionality under a different, and potentially more descriptive, name.

Swift 4.1 compactMap for lazy collections

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