One of the additional features of
tolua++ is the support for class templates, by using the
TOLUA_TEMPLATE_BIND directive. For example:
class vector {
TOLUA_TEMPLATE_BIND(T, int, string, Vector3D, double)
void clear();
int size() const;
const T& operator[](int index) const;
T& operator[](int index);
void push_back(T val);
vector();
~vector();
};
The
TOLUA_TEMPLATE_BIND directive has to be the first thing on the class declaration, otherwise it will be ignored. This code will create 4 versions of the class
vector, one for each type specified on the
TOLUA_TEMPLATE_BIND parameters, each replacing the macro
T (specified as the first argument of
TOLUA_TEMPLATE_BIND). Thus, the functions
operator[],
&operator[] and
push_back will have different signatures on each version of the object. The objects will be recognized as
vector<type> on further declarations, and the name of the table on Lua will be
vector_type_. Thus, the following Lua code could be used:
string_vector = vector_string_:new_local()
string_vector:push_back("hello")
string_vector:push_back("world")
print(string_vector[0].." "..string_vector[1])
Similarily, a template with more than 1 macro could be bound, and it could also inherit from another template:
class hash_map : public map<K,V> {
TOLUA_TEMPLATE_BIND(K V, int string, string vector<double>)
V get_element(K key);
void set_element(K key, V value);
hash_map();
~hash_map();
};
结论：tolua++可以进行简单的模板导出。