Dynamic creating of typedef
I'm creating event system. It's based under boost::signals. To make the work easier I'm using typedef for the function signatures.
Everything is okey until I need creating of some new event trought event's system method. I have to create the typedef dynamically on given type to the template function. The problem is the name of typedef.
Some pseudocode I would have:
template<typename EventType>
void create(const string &signalName)
{
typedef EventType signalName;
// ...
}
Is it po开发者_如何学Pythonssible to make such typedef (their names) with some passed string or data or something else? I don't want to make user care about of this.
UPD: So, I have some typedefs list of function signatures - events. I have some templated function for connecting slots, for example. I don't want to force user to input signature by his hands again every time (user is programmer which will use the event system). So I just use my typedefs from special namespace into template argument.
typedefs only matter during compilation. As far as I know it's just an alias for a type.
Template parameters are, by definition, compile time entities. You can not dynamically create template classes on the fly during program execution as far as I am aware.
In this case, I wouldn't go for typedef's. If you want to have several types of events and create them dynamically, you can use a simple class containing the information about the event type. When you have an event, you link it to the event type created before.
Something like this:
class EventType
{
private:
string type;
EventType(string type);
};
class Event
{
private:
string event_name;
EventType *event_type;
Event(string event_name, EventType event_type);
};
...
void create(const string &signalName)
{
EventType *event_type = new EventType("type_x");
Event *event = new Event("event_x", event_type);
}
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