F#元组(Tuples)

元组是逗号分隔的值集合，这些用于创建临时数据结构，将相关值分组在一起。

这里提供了一些示例-

//两个整数的元组。
( 4, 5 )

//字符串元组
( "one", "two", "three" )

//未知类型的元组。
( a, b )

//具有混合类型的元组。
( "Absolute Classes", 1, 2.0 )

//整数表达式的元组。
( a * 4, b + 7)

let averageFour (a, b, c, d) =
   let sum = a + b + c + d
   sum/4.0

let avg:float = averageFour (4.0, 5.1, 8.0, 12.0)
printfn "Avg of four numbers: %f" avg

编译并执行程序时，将产生以下输出-

Avg of four numbers: 7.275000

访问元组数据

元组的各个成员可以使用模式匹配进行判断和打印。

let display tuple1 =
   match tuple1 with
   | (a, b, c) -> printfn "Detail Info: %A %A %A" a b c

display ("Zara Ali", "Hyderabad", 10 )

编译并执行程序时，将产生以下输出-

Detail Info: "Zara Ali" "Hyderabad" 10

printfn "First member: %A" (fst(23, 30))
printfn "Second member: %A" (snd(23, 30))

printfn "First member: %A" (fst("Hello", "Learnfk!"))
printfn "Second member: %A" (snd("Hello", "Learnfk!"))

let nameTuple = ("Zara", "Ali")

printfn "First Name: %A" (fst nameTuple)
printfn "Second Name: %A" (snd nameTuple)

编译并执行程序时，将产生以下输出-

First member: 23
Second member: 30
First member: "Hello"
Second member: "Learnfk!"
First Name: "Zara"
Second Name: "Ali"