Passing shared delegates

[mist]

Do not have time to test code right now but first guess it is 
related to parsing differences for delegates and usual functions. 
Delegates can have shared/const applied to both delegate type 
itself and context of underlying function. Those are different 
beasts and no wonder type system complains.

You may need to try something like "void delegate() shared f" if 
you want delegate type to match method one.