Declare variable with generic type in Swift

Question

I have a line of code from Obj-C:

GPUImageOutput<GPUImageInput> *filter;

How can I convert it to Swift? I try some solutions but it doesn't work :(

var filter = GPUImageOutput<GPUImageInput>
var filter:GPUImageOutput = GPUImageOutput<GPUImageInput>

also: [What's the Swift equivalent of declaring `typedef SomeClass MyType`?](http://stackoverflow.com/questions/26474061) — rintaro, Apr 03 '15 at 13:38

score 2 · Answer 1 · answered Apr 03 '15 at 10:44

This is not a generic in Objective-C. Obj-C does not support generics.

That notation is used to indicate protocol conformance. So it is declared as a GPUImageOutput that implemente the GPUImageInput protocol.

I believe it can be translated to this in Swift:

var filter: GPUImageInput
// or
var filter: GPUImageOutput

1 Answers1