This returns the type with the arg names we'll actually use. This is
helpful so we can pass values to the right places. We have named edges
so you can actually see what's going on.
Co-authored-by: Samuel Gélineau <gelisam@gmail.com>
This removes the `Close() error` and replaces it with a more modern
Stream API that takes a context. This removes boilerplate and makes
integration with concurrent code easier. The only downside is that there
isn't an explicit cleanup step, but only one function was even using
that and it was possible to switch it to a defer in Stream.
This also renames the functions from polyfunc to just func which we
determine by API not naming.
This adds the requirement that all function implementations provider a
String() string method so that these can be used as vertices in the
pgraph library. If we eventually move to generics for the pgraph DAG,
then this might not matter, but it's not bad that these have names
either.
This flattens the type unification of the map function so that the
solver has more to work with. It's possible that some scenarios might
solve faster, or without recursion, after this improvement.