weird member lookup.swift

// Xcode 8.3b1 (8W109m)

import Foundation

struct Box<T> {
    let value: T
    
    init(value: T) {
        self.value = value
    }
    
    init(_ value: T) {
        self.value = value
    }
}

@objc protocol FooDelegate {
    func foo(_ foo: Foo, didSomethingAt index: Int)
}

class Foo: NSObject {
    weak var delegate: FooDelegate?
}

class UseFoo: NSObject {
    var foo: Foo!
    
    func referToMemberFooAsAny() {
        
        foo = Foo()
        foo.delegate = self
        
        takesAny(foo) // self.foo
        
        takesArray([foo]) // self.foo(_:didSomethingAt:)
        
        takesArray([foo as Foo]) // self.foo
        
        takesDict(["foo": foo]) // self.foo(_:didSomethingAt:) ?!
        
        takesBox(Box(value: foo)) // self.foo(_:didSomethingAt:)
        
        takesBox(Box(foo)) // self.foo !?!??!
    }
    
    func takesAny(_ value: Any) {
        print(value)
    }
    
    func takesArray(_ array: Array<Any>) {
        print(array)
    }
    
    func takesDict(_ dict: Dictionary<String, Any>) {
        print(dict)
    }
    
    func takesBox(_ box: Box<Any>) {
        print(box)
    }
}

extension UseFoo: FooDelegate {
    func foo(_ foo: Foo, didSomethingAt index: Int) {
        print("foo \(foo) did something at \(index)")
    }
}

Xcode 8.2.1 and earlier infer self.foo in each case.