basic() { name = "cltree.basic"; }

std::string repr() { return name+"()"; }

std::string name;

symbol_wrapper(PyObject* /*self*/): symbol() {

name = "cltree.wrapped_symbol";

}

variable_wrapper(PyObject* /*self*/): variable() {

name = "cltree.wrapped_variable";

}

// This constructor is introduced only because cannot use

// boost::noncopyable, see below.

variable_wrapper(PyObject* /*self*/,variable v): variable(v) {}

{

boost::python::class_<basic>("basic")

.def("__repr__",&basic::repr)

;

boost::python::class_<constant, boost::python::bases<basic>, boost::noncopyable>("constant")

;

boost::python::class_<symbol, symbol_wrapper, boost::noncopyable>("symbol")

;

boost::python::class_<variable, boost::python::bases<basic>, variable_wrapper>("variable")

;