[Cython] Fused types syntax

In looking at merging fused types, it's time to nail down the syntax. The current implementation is ctypedef cython.fused_type(list, dict, object) fused_t This requires an addition to the grammer to allow the "call" syntax in a type declaration, as well as special casing to make it allowed only in a typedef. What about cython.fused_type[list, dict, object]. One advantage is that indexing is already valid in type declarations, and its the typical syntax for parameterized types. Thoughts? Any other ideas? - Robert P.S. Anyone remember buffers and C++ templated types are dissallowed as typedefs?