Open Radar

 
Summary:
Block literals have trouble inferring its type, when the type conforms to multiple protocols. This only happens in certain circumstances.

Steps to Reproduce:
The following example will not compile in Xcode 7 beta 1:

protocol A {
    var x: B { get set }
}

protocol B {}
struct B1:B {}

struct M: A, B {
    var x: B
}

func f(bs: [B->B]) -> B {
    return B1()
}

f([ { M(x: $0) } ]) // '(B) -> M' is not compatible with expected type 'B -> B'



Expected Results:
Should compile, as there's enough information for the compiler

Actual Results:
Does not compile unless the type is explicitly added in the last line of the sample code:

f([ {b -> B in M(x: b) } ])  // ok

Version:
Xcode 7 beta (7A120f)