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Summary:
In swift 1.2 when a function takes a type that must conform to a protocol as its argument is passed a type that does not conform to the protocol the error message does not direct the user to the root problem.  

example from attached playground
func create<T: ProtocolA>(T.Type) -> T? {
    return T()
}
let foo = create(classA)// works: classA conforms to ProtocolA
let bar = create(String)// error since String does not conform to ProtocolA but the error is the misleading "Cannot invoke 'create' with no arguments"

Steps to Reproduce:
Open the attached playground in Xcode 6.3 (6D570) and note the error on line 20.  

let bar = create(String) //error "Cannot invoke 'create' with no arguments"

Expected Results:
Since the argument on line 20 does not conform to the protocol an error is expected.  But it would be helpful if the error was a bit more helpful.  Something like "Argument does not conform to 'ProtocolA'"


Actual Results:
The error message is "Cannot invoke 'create' with no arguments" which is confusing since I did supply an argument and in the previous line supplying a type worked fine.

Version:
Xcode 6.3 (6D570)
Swift 1.2
OS X 10.10.3

Notes:
Contents of playground
protocol ProtocolA {
    init()
}

class classA : ProtocolA {
    required init() { }
}

func create<T: ProtocolA>(T.Type) -> T? {
    return T()
}

let foo = create(classA)
let bar = create(String)


Configuration:
in Xcode 6.3 (6D570) with Swift 1.2. Both in a playground and building an iOS app.

Attachments:
'no_args.playground.zip' and 'genericsError.png' were successfully uploaded.