Re: [Swig-user] Boolean expression as array size causing syntax error (Python and C)

[William S F. <ws...@fu...>]

On 03/08/11 15:26, Stefan Zager wrote:
> On Thu, Jul 28, 2011 at 4:29 PM, Shi Hu <fin...@gm...
> <mailto:fin...@gm...>> wrote:
>
>
>     Hi,
>
>     I am trying to build a bridge between Python and C. I am not sure why I
>     can't do this in my interface/header file: int array[(int) 3 > 2].
>
>     In another word, it seems that SWIG can't take boolean expression as the
>     size of an array. But this is legitimate in C.
>
>     For details, when I do: swig -python example.i, SWIG gives example.i:9:
>     Error: Syntax error in input(1) as the error message.
>
> I don't think this is a big surprise.  For SWIG to process that
> correctly, its parser would have to be a great deal more complex -- it
> would have to evaluate the expression '(int) 3 > 2'.  I think that's
> beyond the scope of this project.
>
Indeed the expression is unusual, but the goal of SWIG is to parse any 
valid C/C++, so this ought to be fixed. However, given the tiny number 
of SWIG developers and the fact it is an obscure case, it isn't likely 
to get fixed in a rush though by any developers. Anyone can debug and 
fix the SWIG source though, so patches are always welcome.

William