// 'name' is inferred to be a string based on usage.let printMessage name =    printfn $"Hello there, {name}!"// 'names' is inferred to be a sequence of strings.let printNames names =    for name in names do        printMessage namelet names = [ "Ana"; "Felipe"; "Emillia" ]printNames names

let square x = x * xlet isOdd x = x % 2<> 0let sumOfOddSquares nums =    nums    |> List.filter isOdd    |> List.sumBy squarelet numbers = [1; 2; 3; 4; 5]let sum = sumOfOddSquares numbersprintfn "The sum of the odd squares in %A is %d" numbers sum

type Shape =    | Square of side: double    | Rectangle of width: double * length: doublelet getArea shape =    match shape with    | Square side -> side * side    | Rectangle (width, length) -> width * lengthlet square = Square 2.0printfn $"The area of the square is {getArea square}"

type Customer(firstName, middleInitial, lastName) =    member this.FirstName = firstName    member this.MiddleInitial = middleInitial    member this.LastName = lastName    member this.SayFullName() =        $"{this.FirstName} {this.MiddleInitial} {this.LastName}"let customer = Customer("Emillia", "C", "Miller")printfn $"Hello, I'm {customer.SayFullName()}!"