<@U0AAQKT9Q> Ok. Did not know that `T` can be subs...

# language-proposals

[juangamnik]

@ilya.gorbunov Ok. Did not know that T can be substituted with an optional type. I thought you have to use T? then. I don't know whether it is a good idea to replace T with some T'? with T': T because then the code expects instances of T not to be null, so that t.foo() would be Ok for the compiler (declaration-site) although it may be an NPE... I will test this with Kotlin 1.0.3 🤓. But if it is ok for the compiler, a corresponding implicit Boolean flag parameter could be used...