"'(', '.', '[' or ']' expected, got ','" error on valid code

[DetachHead]

function foo {
    [Windows.UI.Notifications.ToastNotificationManager, Windows.UI.Notifications, ContentType = WindowsRuntime] > $null
}

i have no idea what this is because i just pasted it from here, but it's valid

[ForNeVeR]

I believe it is some special syntax to specify the way you want to load the type (in this case, from a Windows.UI.Notifications winmd assembly, or whatever they are called these days?).

Definitely an issue of our parser.