Swift中的Int vs Integer

Question

Does anyone know what the difference is between these two types?

The docs only refer to Int but Xcode 6 auto complete only gives me Integer when I type. I started using Integer when porting code only to find that you have to cast between the two types.

For instance the following code gives the error Could not find an overload for '+' that accepts the supplied arguments .

var number1 : Int = 5
var number2 : Integer = 10
number1 + number2

Answer 1

An Int is the type whilst an Integer is a protocol it implements.

You should be using Int in declarations, ie:

var num: Int = 5

which is also the type that's inferred for integer literals when a type isn't specified, ie:

var num = 5