Transforming data models is actually a key activity of any program. Swift provides us with Higher Order Functions that perform specific transformations on the collection.
The flatMap(_:) function takes a closure defining an element’s transformation within a collection. Swift language offers flexibility in writing closures in full or shortened form. Additionally, KeyPath can be utilized to specify the relevant parameter. For comparison, we’ll also present a straightforward implementation using a for loop.
Measure the Higher Order Functions - Flat Map
attempts: 10, repeats: 100 000
| Name | Duration | Deviation | Scale | |
|---|---|---|---|---|
| 1. | Control Flow method | 160.23 ms | + 0% | .......... |
| 2. | Closure parameter | 160.76 ms | + 0% | .......... |
| 3. | Shorthand argument | 160.90 ms | + 0% | .......... |
| 4. | Key Path | 181.61 ms | + 13% | ........... |
Our base implementation of the flat mapping function using a for loop is the most efficient way to transform a set into another collection. Although the differences are minor, this implies that the flatMap(_:) function itself is more intricate.
Calling the algorithm with a path results in a 20% performance decrease compared to other methods. While this drop in performance may be negligible with a small dataset, it’s worth noting.