Method evalExpression

src/App/DocumentObjectPyImp.cpp:452–482

}

PyObject* DocumentObjectPy::evalExpression(PyObject* self, PyObject* args)
{
    const char* expr;
    if (!PyArg_ParseTuple(args, "s", &expr)) {
        return nullptr;
    }

    // HINT:
    // The standard behaviour of Python for class methods is to always pass the class
    // object as first argument.
    // For FreeCAD-specific types the behaviour is a bit different:
    // When calling this method for an instance then this is passed as first argument
    // and otherwise the class object is passed.
    // This behaviour is achieved by the function _getattr() that passed 'this' to
    // PyCFunction_New().
    //
    // evalExpression() is a class method and thus 'self' can either be an instance of
    // DocumentObjectPy or a type object.
    App::DocumentObject* obj = nullptr;
    if (self && PyObject_TypeCheck(self, &DocumentObjectPy::Type)) {
        obj = static_cast<DocumentObjectPy*>(self)->getDocumentObjectPtr();
    }

    PY_TRY
    {
        std::shared_ptr<Expression> shared_expr(Expression::parse(obj, expr));
        if (shared_expr) {
            return Py::new_reference_to(shared_expr->getPyValue());
        }
        Py_Return;
    }
    PY_CATCH
}