I no longer think inline delegate declarations are necessary, because if one is lazy and don't want to declare the delegate on a separate line, one can use a generic delegate:
void foo(func as Converter<String, int>) # Eq. to declaring a delegate "sig DelegateName(str as String)"
x = func("hi there")
Such generic delegates are provided by the .NET framework for most common scenarios (Func<> up to 4 params, and Action<> up to 4 params as well, where the difference is that Action has no return value). It would be interesting if Cobra provided its own version of such general purpose delegates, so that they can be used in other backends. By the way, Cobra seems to be able to consume generic delegates coming from a dll, but chokes when it sees one declared in a Cobra file. I don't know if that's a bug or a missing feature, but in any case it shouldn't be too hard to fix (I think the priority of that is low, though, since as I said .NET comes "preloaded" with all generic delegates that one might reasonably need).