[Pyrex] Wrapping a (void *) cookie

[Greg Ewing]

jkoshy at FreeBSD.ORG (Joseph Koshy) writes:

> I'd like to write a class in Pyrex that wraps a C 'handle' or 'cookie'.
> 
> For example:
> 
>     ---"cookie.pyx"---
>     cdef extern from *:
>       ctypedef void * cookie
>       cookie cookie_factory()
>       void cookie_eater(cookie c)
>     ---
> 
> However, the following is rejected:
> 
>     ---"cookie.c"--
>     cdef class Cookie:
>       cdef cookie c
>       def __new__(self, cookie c):
> 	self.c = c

Presumably, cookies are opaque objects that can only be
created by calling cookie_factory(), right? In that case,
instead of trying to pass a cookie into the constructor,
have the constructor call cookie_factory:

  cdef class Cookie:
    cdef cookie c
    def __new__(self):
      self.c = cookie_factory()

  def eat(Cookie c not None):
    cookie_eater(c.c)

Greg Ewing, Computer Science Dept, +--------------------------------------+
University of Canterbury,	   | A citizen of NewZealandCorp, a	  |
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greg at cosc.canterbury.ac.nz	   +--------------------------------------+