Remove all instances of an object from an array
Swift version: 5.6
Arrays already have methods to find and remove a single item, or remove all items at once, but for removing all instances of a specific item you need to use a closure-based method called removeAll(where:).
For example, given these numbers:
var numbers = [2, 1, 2, 3, 2, 4, 2, 5]If we wanted to remove all instances of 2 from that array, we could use removeAll(where:) like this:
numbers.removeAll { $0 == 2 }If you want to return the array with items removed rather than doing it in place, you’d need to write your own extension to Array, like this:
extension Array where Element: Equatable {
func removing(_ obj: Element) -> [Element] {
return filter { $0 != obj }
}
}Now you can write let removed = numbers.removing(2) to get back [1, 3, 4, 5].
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Available from iOS 8.0
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