[Ecls-list] How to wrap and return constant pointers with c-inline?

[Peter Enerccio]

Constness of a pointer, in c and c++ means absolutely nothing. It is just a
way for programmer to self policy, same as private/public in c++/java, they
are only for compilers to throw errors and programmers to avoid those
errors. In memory, it is just data, and as data, in c you can force
compiler to represent them in any way, ie cast. Anyways, glad to be help.


2013/7/7 Dietrich Bollmann <dietrich at formgames.org>

> On Sun, Jul 7, 2013 at 9:48 PM, ... <. <enerccio at gmail.com>..> wrote:
>
> Why cant you just cast it in the inline part? (void*) comes to mind...
>>
>
> Because I thought that it is not possible to "cast away" a const
> qualification...
>
> ...But you are completely right:  even if this might not be a good thing
> to do under normal circumstances, it actually is possible and solves the
> problem :)
>
> Thanks for the advice!
>
> Dietrich
>
>
>
> On Sun, Jul 7, 2013 at 8:52 PM, Dietrich Bollmann <dietrich at formgames.org>wrote:
>
>> Hi,
>>
>> How can I wrap and return the constant pointer
>>
>>   const CRhinoCommandContext *context;
>>
>> with c-inline?
>>
>> Using something like
>>
>>   (ffi:c-inline () () :pointer-void "context" :one-liner t)
>>
>> results in the error
>>
>>   error C2664: 'ecl_make_foreign_data' : cannot convert parameter 3 from
>> 'const CRhinoCommandContext *' to 'void *'
>>         Conversion loses qualifiers
>>
>> But I couldn't find something like :const-pointer-void...
>>
>> How can I solve this problem?
>>
>> Thanks,
>>
>> Dietrich
>>
>>
>


-- 
Bc. Peter Vaňušanik
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