[boost] const problem with python interface

From: Victor A. Wagner, Jr. (vawjr_at_[hidden])
Date: 2002-07-10 12:19:03

Using the commented out signature (the one with  .............., const 
std::size_t key,............)
causes errors compiling on VC++.NET
It's not clear why declaring the key const should (in the philosophical 
sense) cause any difficulties.  following the actual thread
of errors was beyond our abilities at the time.  Of course, the original 
"error" didn't mention const anywhere, which didn't make finding the 
problem any easier.

<rant>I sure wish the .NET compiler would give the "called from" trace back 
on all of it's errors/warnings to facilitate finding the perceived 
problems(like VC++6 did).  This one we chased for over  an hour</rant>

TimeStamps is equivalent to std::vector<double>
The error does NOT occur until        time_stamp.def(set_ts_item, 
"__setitem__");       is added to the source.  That is, if the line is 
removed, there is no error, but of course, we can't access set_ts_item either.
========================================================

// Sets the item corresponding to key in the map.
//void set_ts_item( TimeStamps& self, const std::size_t key, const double& 
value)
void set_ts_item( TimeStamps& self, std::size_t key, const double& value)
{
self.at(key) = value;
}

#include <boost/python/class_builder.hpp>
namespace python = boost::python;
BOOST_PYTHON_MODULE_INIT(PythonTest)
{
// Create an object representing this extension module.
python::module_builder this_module("PythonTest");
// TimeStamps
python::class_builder<TimeStamps> time_stamp(this_module, "TimeStamps");
time_stamp.def(boost::python::constructor<>());
time_stamp.def(&TimeStamps::size, "__len__");
time_stamp.def(get_ts_item, "__getitem__");
time_stamp.def(set_ts_item, "__setitem__");
}
Victor A. Wagner Jr.      http://rudbek.com
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