[Pyrex] ctypedef problem and improvement

[Greg Ewing]

Serge Barbosa Da Torre <sergiobdt at yahoo.com>:

> Often we are defining some functions which do not = take any
> parameters, or in case of methods do not use the self parameter = at
> all. In these cases, I think it should be easy to suppress the call =
> to PyArg_ParseTupleAndKeywords in the resulting C code.

It would, although I'd still want to put in a check that
no parameters were passed, and it's not clear whether this
would be significantly less expensive than a PyArg_ParseTuple
call with an empty format string. I'll look into this.

> Then what we typically want to do in the pyx file is:
> 
> cdef from "module.h":
>   ctypedef struct MyStruct
> 
> cdef class MyClass:
>   cdef MyStruct thisstruct
> 
> However this is currently not possible: the pyrexc compiler fails the =
> compilation with a "variable type MyStruct is incomplete"

You can lie to it:

  cdef extern from "module.h":
    ctypedef struct MyStruct:
      pass

Greg Ewing, Computer Science Dept, +--------------------------------------+
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