Swift "is" operator with type stored in variable

Question

This piece of code works as expected. "integer is int" is printed in output.

let integer = Int()

if integer is Int {
    println("integer is int")
}
else {
    println("integer is not int")
}

I want to use is operator in the same way as I can use isKindOfClass method - with class (or rather type) stored in variable. It would look like this:

let integer = Int()
let intType : Any = Int.self

if integer is intType {
    println("Integer is int")
}
else {
    println("Integer is not int")
}

Unfortunately this produce an error: Use of undeclared type 'IntType'.

IntType in if condition has even a different color (if you paste it to playground) than in other places in source code, suggesting that (as the error message says) its being treated as a class name (like IntType would be a class). But it isn't. It means that is operator cannot be used with variables on the right side?

I want to use is operator because it can compare not only classes, but also other types.

How can I check if value has type which I expect?

---

I found dirty solution, but it's really far from being reliable...

let integer = Int()
let intType : Any = Int.self

func ==(left: Any, right: Any) -> Bool {
    let leftString = "\(left)"
    let rightString = "\(right)"
    return leftString == rightString
}

if (integer.dynamicType as Any) == intType {
    println("true")
}
else {
    println("false")
}

Works perfect, but be careful - cause this one is also true:

if (integer.dynamicType as Any) == ("Swift.Int" as Any) {
    println("true")
}
else {
    println("false")
}

Is there a better way?

---

Ok, I'll explain further what do I want to achieve. I have object which manages instances of generic class instances. At some point I need to pick one of those generic class instances basing on type of generic. Example:

class GenericClass<T> {}

struct ToolInfo {
    let tool : AnyObject
    let jobType : Any
}

class Manager {
    var tools = Array<ToolInfo>()

    func pickToolForTheJob(job : Any) -> AnyObject {
        return tools.magicMethodWhichReturnProperTool()
    }
}

let viewTool = GenericClass<UIView>()
let rectangleTool = GenericClass<CGRect>()

let manager = Manager()
manager.tools.append(ToolInfo(tool: viewTool, jobType: UIView.self))
manager.tools.append(ToolInfo(tool: rectangleTool, jobType: CGRect.self))

manager.pickToolForTheJob(UIView()) // i want to get viewTool here
manager.pickToolForTheJob(CGRect()) // i want to get rectangleTool here

Currently i have ToolInfo struct, because as far as I know its not possible to get type passed in <> while instantiating generic class object. But I'm still unable to compare it.

Answer 1

It means that is operator cannot be used with variables on the right side?

Correct. The right side of is must be hard-coded at compile-time.

If you don't need polymorphism and your types are class types, you can use === to compare the dynamicType of an instance with a class type. That's the only way you're going to get a type-in-a-variable on the right side of something in pure Swift.