This is an interesting question. PartialPlus doesn't actually introspect _before_ calling, and I think this is a good argument for why it shouldn't. There are two issues that are somewhat distinct:

1. `getargspec` and `__code__` do not work with functions implemented in C (which do not support pylearn2's calling convention of passing positionals by name). This, unfortunately, we can't do anything about.
2. We don't have any way of making positional calls from YAML.

I think our best bet for addressing 2) is with an implicit resolver, but it's slightly tricky work.