[Cython] __next__ | not being able to use cpdef

[Lisandro Dalcin]

I __next__ falls in the category of special methods, please read the fine docs

http://www.cosc.canterbury.ac.nz/greg.ewing/python/Pyrex/version/Doc/Manual/special_methods.html

Declare __next__ with 'def', they are treated specially and are as
fast as the CPython implementation permits.

On Sat, Dec 6, 2008 at 12:23 PM, Jelle Feringa <jelleferinga at gmail.com> wrote:
> Hi,
> I just started to use Cython, for writing a set of fast iterators.
> Go easy on me, this is all new territory ;')
> Now, the thing is that if I understood correctly, it would be faster to have
> the __next__ method types a cpdef int __next__(self )
> When I do so the module fails to compile.
> Is there a specific reason why this is so?
> Still, using the object below, accessing objects from an iterable is twice
> as fast.
> Thanks,
> -jelle
> cdef class FastLoopObj1d:
>
>
>
>     cdef int N, i
>     cdef object obj
>
>
>
>     def __init__(self, n, obj ):
>         self.N = n-1
>         self.i = 0
>         self.obj = obj
>     def __iter__(self):
>         return self
>
>
>
>     # no cpdef allowed?
>     def __next__( self ):
>         if self.i < self.N:
>             self.i+=1
>             return self.obj[self.i]
>         else:
>             raise StopIteration
>
>
>
> _______________________________________________
> Cython-dev mailing list
> Cython-dev at codespeak.net
> http://codespeak.net/mailman/listinfo/cython-dev
>
>



-- 
Lisandro Dalcín
---------------
Centro Internacional de Métodos Computacionales en Ingeniería (CIMEC)
Instituto de Desarrollo Tecnológico para la Industria Química (INTEC)
Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)
PTLC - Güemes 3450, (3000) Santa Fe, Argentina
Tel/Fax: +54-(0)342-451.1594