comment on

Hi. My question concerns how one defines in XS that one has a C++ class. The only docs I can find on the subject of using XS with C++ is in the XS reference manual so I am trying to run their example but it is failing on "make" and the error indicates that the compiler is not recognizing the language as C++, so it doesn't recognize the class. This would make sense since it is compiling a .c file, namely myclass.c. I am confused. No matter what I do, it seems that xsubpp generates a .c file and never a .cc file. But if this is the case, then how will it ever recognize class declarations? Or is it saying that I have not supplied a class definition? What am I missing? Here's the output of "make":

cc -c   -O     -DVERSION=\"0.01\"  -DXS_VERSION=\"0.01\" -Kpic -I/usr/
+local/lib/
perl5/sun4-solaris/5.00405/CORE  myclass.c
"/home/judyf/perlwork/myclass/myclass.h", line 9: undefined or not a t
+ype: class
"/home/judyf/perlwork/myclass/myclass.h", line 9: syntax error before 
+or at: col
or
"/home/judyf/perlwork/myclass/myclass.h", line 9: undefined or not a t
+ype: color
"/home/judyf/perlwork/myclass/myclass.h", line 15: syntax error before
+ or at: /
"/home/judyf/perlwork/myclass/myclass.h", line 23: syntax error before
+ or at: in
t
"/home/judyf/perlwork/myclass/myclass.h", line 24: cannot recover from
+ previous
errors
cc: acomp failed for myclass.c
*** Error code 2
make: Fatal error: Command failed for target `myclass.o'
[download]

Here's the class declaration from the myclass.h file:

class  color {
        public:
        color();
        ~color();
        int blue();
        int set_blue( int );

        private:
        int c_blue;
};
[download]

Here's the relevant .xs code:

int
color::blue()

void
color::set_blue( val )
        int val
[download]

My instinct would be, in the myclass.xs file, to create a new package within the one module (called "color") but based on the reference manual doc, I refrained from doing this and kept the class method declaration under the one package (with same name as module). hence, in myclass.xs:

MODULE = myclass                PACKAGE = myclass
[download]

Here's the relevant portion of typemap file:

color *                 O_OBJECT

OUTPUT
# The Perl object is blessed into 'CLASS', which should be a
# char* having the name of the package for the blessing.
O_OBJECT
        sv_setref_pv( $arg, CLASS, (void*)$var );

INPUT
O_OBJECT
        if( sv_isobject($arg) && (SvTYPE(SvRV($arg)) == SVt_PVMG) )
                $var = ($type)SvIV((SV*)SvRV( $arg ));
        else{
                warn( \"${Package}::$func_name() -- $var is not a bles
+sed SV ref
erence\" );
                XSRETURN_UNDEF;
        }
[download]

Here's Makefile.PL (where I set 'XSOPT' to tell it I'm using C++):

use ExtUtils::MakeMaker;
WriteMakefile(
    'NAME'      => 'myclass',
    'VERSION_FROM' => 'myclass.pm', # finds $VERSION
    'LIBS'      => [''],   # e.g., '-lm'
    'DEFINE'    => '',     # e.g., '-DHAVE_SOMETHING'
    'INC'       => '',     # e.g., '-I/usr/include/other'
    'XSOPT'     => '-C++',
);
[download]

Thanks for your help.

In reply to using XS with C++ by juda

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