Having to pass all input and output refs to build function.

[Mearman]

Breaking this out from #2308
Is there any way to call the build function without having to explicitly pass references to all input and output ports?
Without it, it's not possible to have an anonymous inline input or output nodes.

allows TypeScript to understand at compile time what the signature of the board definition is

[Mearman]

closing this issue until I have a clearer example