Hi,
> >The xsubpp compiler doesn't support C++'s template facilities.
> >We need to define typemaps for each template instance as follows:
> >
> >typedef vector<int> IntVector;
> >typedef vector<string> StringVector;
> >
> >IntVector T_INT_VETOR
> >StringVector T_STR_VECTOR
>
> With a little work I am sure we could avoid the typedef
> and have typemap just say
>
> vector<int> T_VECTOR_INT
> vector<string> T_VECTOR_STRING
It seems that Inline::CPP doesn't support a typemap like that.
I got the following enrror when didn't use typedef.
Can't locate auto/main/test_int_vector.al in @INC...
The xsubpp doesn't consider C++ namespaces, and hence treat
vector<int> differently from std::vector<int>.
Therefore I think using typedef still have a little effectiveness.
> The structure there is a feature of vector-ness. The only
> part that differs is the element to/from SV conversion.
Yes I knew that, but couldn't work out a solution.
> You cannot overload on return type unfortunately, so guts
> a generic T_VECTOR might look like
>
> template elemtype
> ....
> elemtype elem;
> sv_to_type(sv,elem);
> var.push_back(elem);
>
> The fun part of that is trying to devise a template scheme so that element types
> of int, char, long etc do SvIV () while char *, string etc. do SvPV
> and float, double to SvNV(). Might be easier just to have a set of
> overloaded functions:
>
> inline void sv_to_type(SV *sv,int &elem) { elem = SvIV(sv) }
> inline void sv_to_type(SV *sv,double &elem) { elem = SvNV(sv) }
That's an interesting idea, but still has a redundancy.
I think I want to apply existing typemaps to each template element,
but it requires the xsubpp to scan code recursively, and process
additional task.
If I have a good idea for that, I'll try to write a patch for the xsubpp.
> It probably makes sense (it often does IMHO) to make the typemap call
> a function - that function can be in C++ part of the .xs file and
> so be overloaded or templated in C++ way - but we need to find a way to
> get $elemtype in this fragment:
>
> T_VECTOR
> $elemtype dummy;
> sv_to_vector($arg,$var,dummy)
>
> By looking at the xsubpp code we _may_ be able to find a way to fish
> $elemtype out of vector<elemtype>
--
SH <[EMAIL PROTECTED]>
Livin' on the EDGE Co., Ltd.
