Dynamically pass in type to MemoryLayout<T> in Swift

Question

I would like to create a function like this:

func getStride(_ type: T.Type) {
  return MemoryLayout<type>.stride
}

But it doesn't work .

I would like to be able to call it like this:

getStride(Bool) //=> stride value

If not that, then perhaps this:

getStride(Bool.self)

Wondering if anything like this is possible.

Answer 1

You have to define a generic function, then you can refer to MemoryLayout<T> with the same type that was passed to the function:

func getStride<T>(_ type: T.Type) -> Int {
    return MemoryLayout<T>.stride
}

print(getStride(Bool.self)) // 1
print(getStride(Double.self)) // 8