Re: how to avoid pulling in Win32 include "world" for mutex

* Alf P. Steinbach:


I meant, the usual PIMPL idiom,

   class Mutex
   {
       class Impl;
       Impl* pImpl;
   public:
       ...
   };

The corresponding compiler firewall idiom of a providing a factory
function for an abstract class,

  class AbstractMutex
  {
  public:
      virtual ~AbstractMutex() {}
      ...
  };

  std::auto_ptr<AbstractMutex> mutex();

does not even require a forward declaration of the implementation class,
but at the cost of preventing the client code from defining derived
classes with the desired functionality. It appears that some use the
term "PIMPL" also for this.

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