[Cython] Fused Types

[Pauli Virtanen]

Fri, 29 Apr 2011 10:23:55 +0200, mark florisson wrote:
[clip]
> Ok, branching on the type sounds fine to me. It brings one problem
> though: because you cannot declare the variables of your variable type
> (the type of say, mystruct.attrib), you will need to do multiple
> declarations outside of your branches. So in my example:
> 
> cdef func(struct_t mystruct, int i):
>     cdef string_t string_var
>     cdef int int_var
> 
>     if typeof(mystruct) is typeof(int):
>         int_var = mystruct.attrib + i
>         ...
>     else:
>        string_var = mystruct.attrib + i
>        ...
> 
> But this is probably not a common case, so likely not an issue.

Are you planning to special-case the "real_t complex" syntax? Shooting 
from the sidelines, one more generic solution might be, e.g.,

	ctypedef cython.fused_type(A, B) struct_t
	ctypedef cython.fused_type(float, double, paired=struct_t) real_t
	ctypedef cython.fused_type(int_t, string_t, paired=struct_t) var_t

and just restrict the specialization to cases that make sense.

-- 
Pauli Virtanen