Question

I have a serious problem with calling references in my php code. I wrapped my c++ class with swig and want to call the method, after I read the manual I figured out that, in SWIG when there is a reference in c++ arguments we have:

class foo {
Public;
double bar(double &a);
}

in swig wrapper class we have:

double foo_bar(foo *obj,double *a) {
obj->bar(*a);}

I totally understand that, my question is how can I call the method bar in PHP code?
I started with:

$ptr_a = &$a
$obj->bar($ptr_a);

but it doesn’t work. Any idea???

Answer 1

I had a go with using phppointers.i and the REF typemap to create something that used the PHP concept of a reference. I couldn’t get that to work, but the standard, language neutral SWIG approach to handling things like this with cpointer.i worked just fine:

%module test

%include <cpointer.i>

%pointer_class(double,Double);

%inline %{
  void func(double& a) {
    a = -666.0;
  }
%}

Worked as expected with:

<?php
include('test.php');
echo "testing\n";
$a=new Double(0.0);
test::func($a);
echo "In PHP: " . $a->value() . "\n";
?>