Lisandro Dalcin wrote:
> On Thu, May 14, 2009 at 4:08 PM, Dag Sverre Seljebotn
> <[email protected]> wrote:
>> Robert Bradshaw wrote:
>>> Does this have a performance impact compared to the other way? It
>>> does bloat the code some. (Maybe it's not critical anyways.)
>
> Give me a bit more of time to give a definitive comment on this, but ...
>
>> Well, it is only used for external typedefs, and considering that the
>> bug is quite critical (basically it's very easy to do *(long
>> long*)&some_short)...
>>
>> Haven't benchmarked it, we could consider switching to my original
>> proposal later..
>>
>
> ... as long as the "property" is defined with a C protocol (instead of
> the Python-side "property" builtin), I do not expect a impact on
> performance.
>
>> Lisandro, would you like to argue why you were -1?
>>
>
> For the same rationale that othes gave on this thread (basically, the
> impact on C semantics), and because I believe a better and backward
> compatible solution can be found.
>
> Simplifying the whole type system seems a mistake to me, in the
> temptation to guess, I would just guess ONLY in the case of external
> ctypedef's. Moreover, we could extend this to make "ctypedef signed
> value" as an unknown-size integral, but if the code does "ctypedef int
> value", assume that the ctypedef is actually a "int" and treat it like
> that. Of course, we have a problem with floating poing. Then perhaps,
> you should enable a special declarations for integrals and floatings
> like this:
>
> ctypedef signed integral i
> ctypedef unsigned integral j
> ctypedef floating x # or "floatingpoint", or "inexact"
>
> and ONLY in such case we treat such declarations as unknown-size types.
>
> Does this make sense?
Sure :-) But I was mainly referring to
"""
My suggestion for a fix here is to replace all T_INT, T_UINT etc. with
simply three types: __Pyx_T_SIGNED, __Pyx_T_UNSIGNED, __Pyx_T_FLOAT.
These would use sizeof to determine the right type to flag the extension
type property as (like Lisandro did with T_SIZET already does).
"""
This is ONLY used when you do
cdef class A:
cdef public sometype FOO
I.e. in my point (A) I was only arguing collapsing types for the purpose
of exporting properties (through the CPython member structures).
If you misunderstood my intentions I suppose that answers the question...
Dag Sverre
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