Build sequences efficiently using result builders!
let array = Array {
1
[2, 3, 4, 5]
if Bool.random() {
CollectionOfOne(6)
}
"7,8,9".split(separator: ",").lazy
.map(String.init)
.compactMap(Int.init)
if Bool.random() {
[10]
} else {
[10] as Set
}
}