macros - Is it possible in C++ to loop over all subclasses of an Abstract class? -

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I have an abstract class in C ++ with many subclasses.

Is it possible to do something like macros or template metaprogramming something like this: 

  Base suburban of the base: mymap [subclass :: SOME_CONSTANT] = new subclass ();    
 
 
 No, you can not.  
 What you want, apparently, is a  factory  (or perhaps  abstract factory ).  
 In C ++, you set up a factory class and register builders.  
  class FooFactory {public: typed characters  second) (); } Private: std :: map & lt; Std :: string, builder & gt; _Map; };   
 In order to register derivative classes during the library load, you can create a singleton of this factory, which is easy for plug-in architecture:  
  FooFactory & amp; GetFooFactory () {Fixed FooFactory F; Refund F; }   
 And you can prepare an easy builder:  
  template & lt; Typename derived & gt; Foo * Füblilder () {New result (;); }   
 Then people are expected to register their derivative classes in the factory:  
  Static Const. Bool registered times = GetFooFactory (). Register ("bar" fooBuilder & lt; bar & gt;); Note: It is not necessarily far away that the factory should be singleton, although it is not as bad as it once loads the load of libraries once it is finished.  
 Note: For a proper plugin architecture, you have to use RAII (instead of the bowl) to handle the unknowment in the library unload. This is very rare.

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