Use Sets in Swift

Written by Team Kodeco

A set is an unordered collection of unique elements. Sets are useful for storing data when you need to check for the presence of an element, but don’t need to know its order or where it appears in the set.

Here’s an example of how to create and use a set:

// create a set with an array literal
var favoriteColors: Set = ["red", "green", "blue"]

// add an element to the set
favoriteColors.insert("purple")
print(favoriteColors) // ["purple", "red", "blue", "green"]

// check if an element is in the set
let isYellowInSet = favoriteColors.contains("yellow")
print(isYellowInSet) // false

// remove an element from the set
favoriteColors.remove("green")
print(favoriteColors) // ["purple", "red", "blue"]

You can also create an empty set using the Set() initializer:

var emptySet = Set<String>()

It is important to note that sets in Swift are value types, which means they are copied when they are passed as a function argument or assigned to a variable. Also, sets use a hash value to identify its elements, which means that the order of elements in a set may not be predictable.