Swift Learning meta-group

There is no tuple in OC. In Swift, the new addition, the OC array concept is still thinking that since the same type of elements can be stored, the different types of elements have nothing to store it, the answer is very sad, OC does not have the concept of a tuple. Only Swift added this thing, it is also very interesting, the following is my personal understanding of the tuple, assuming that there is not correct, please point out, common progress, thank you

A tuple (touples) is a collection of different data types that can be stored, denoted by (), a chestnut

Let Touples = ("Xiaoyu", +, "math", 98.5)
println (Touples)

If you see a hint, you should know that we can go through touples.0 or. 1 or. 2 or. The elements of a tuple, which are judged by the type of swift to know the corresponding data type

We can also create tuples in a different way

Let (name,_,_,score) = Touples

The above _ is a wildcard character in Swift. Remember to ignore the meaning that you do not need the corresponding value, do not need

println (name)
println (Score)

In fact I personally prefer the third way, clear, code is easier to read

Let Touple = (name: "Xiaoyu", Age:16,souce: "Math", scores:98.5)
println (Touple.name)

Said the above a big push, I still do not know the tuple can do what, Balabala. Just know how to create, read and so on. So what can we do with this meta-group of Little friends, and here's a little chestnut.

Override Func Viewdidload () {              var touple = (name: "Xiaoyu", Age:16,souce: "Math", scores:98.5)        println ( Touple.name)        Swapme (&touple.name, B: &touple.souce)        println (touple)           }    func swapme<t > (inout a:t,inout b:t) {Let        temp = a        a = b        b = Temp    }

Using the code above, we secretly swapped math and name, (note that this can only be exchanged for the shape of the same type, T is a generic expression), but we learned that the tuple would be able to write

    Func swapme<t> (inout a:t,inout b:t) {        (A, b) = (b,a)    }

Well. can achieve the same effect, do not believe, and then an array to do the experiment

        var Temparr = [5,7]        Swapme (&temparr[0], B: &temparr[1])        println (Temparr)

Well, that's a real thing to do.

There is the yuan group really put anything can ah. Do not believe can try the following actions

        var num =        println (num)        println (num.0.0.0.0)

Tuples also have a practical place for error handling, and can put errors directly in the tuple to return

References: The Book of the Meow God

Swift Learning meta-group