[Boost-users] [mpl] Instantiating a vector of factory functions

From: Dan Posluns (dan_at_[hidden])
Date: 2007-09-14 21:11:03

Okay, I'm a lot closer to my goal of having an automated factory of 
objects that are dynamically polymorphic but have their inheritance set 
up through static means.

What I have now is something like this:

// My factory template
template<class Base, class Derived>
struct Factory
{
    Base *create()   { return new Derived(); }
};

// My vector of factories for the different Derived types
typedef mpl::vector<
    Factory<Base, Derived1>,
    Factory<Base, Derived2>,
    Factory<Base, Derived3> > MyFactories;

(I actually use MPL to automatically cross and combine different 
classes, which is pretty cool.)

Now I could create a vector of the same length with every type as a 
pointer to a Factory function, and with Fusion I could probably 
instantiate it (although I haven't got that working yet). But that still 
wouldn't get me what I want, which is a table of those factory functions 
that I can index into at run-time.

Can anyone suggest a technique for doing this?

Thanks,

Dan.

-- 
Dan Posluns, B. Eng. & Scty. (Software Engineering and Society)
dan_at_[hidden] - ICQ: 35758902
http://www.danposluns.com
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