可以比较元组是否相等(从 Swift 2.2/Xcode 7.3.1 开始)，但是它们不符合 Equatable 协议.因此你有使用 indexOf 的基于谓词的变体来定位元组在一个数组中.示例:

Tuples can be compared for equality (as of Swift 2.2/Xcode 7.3.1), but they do not conform to the Equatable protocol. Therefore you have to use the predicate-based variant of indexOf to locate a tuple in an array. Example:

let valueArray = [("a", "b"), ("c", "d")]
let tuple = ("c", "d")
if let index = valueArray.indexOf({ $0 == tuple }) {
    print("found at index", index)
}

在 Swift 4 中，该方法已重命名为 firstIndex(where:):

In Swift 4 the method has been renamed to firstIndex(where:):

if let index = valueArray.firstIndex(where: { $0 == tuple }) {
    print("found at index", index)
}