swift - 为什么带有可变参数的swift函数不能接收数组作为参数

Question

如题，为什么swift可变参数不能接收数组作为参数？例如:

func test(ids : Int...){
    //do something
}
//call function test like this failed
test([1,3])
//it can only receive argument like this
test(1,3)

有时，我只能获取数组数据，我也需要函数可以接收可变参数，但不能接收数组参数。也许我应该定义两个函数，一个接收数组参数，另一个接收可变参数，除了这个还有其他解决方案吗？

Answer 1

重载函数定义...

func test(ids : Int...) {
    print("\(ids.count) rx as variadic")
}
func test(idArr : [Int]) {
    print("\(idArr.count) rx as array")
}
//call function test like this now succeeds
test([1,3])
//... as does this
test(1,3)

// Output:
// "2 rx as array"    
// "2 rx as variadic"

当然，为了避免重复代码，可变版本应该只调用数组版本:

func test(ids : Int...) {
    print("\(ids.count) rx as variadic")
    test(ids, directCall: false)
}
func test(idArr : [Int], directCall: Bool = true) {
    // Optional directCall allows us to know who called...
    if directCall {
        print("\(idArr.count) rx as array")
    }
    print("Do something useful...")
}

//call function test like this now succeeds
test([1,3])
//... as does this
test(1,3)

// Output:
// 2 rx as array
// Do something useful...
// 2 rx as variadic
// Do something useful...