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Fun with member-function pointers

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I've been working on a project that implements instrument drivers. The API 
uses operation codes to direct behavior. All the drivers are subclasses of a 
common ABC.  In my implementation, I used a method of mapping the op codes 
to handlers for that operation. That was accomplished with pointers to 
member functions.

Someone asked me why I didn't have the handler storage and lookup in the 
base class. My initial response was that the pointers had different types. 
Then I got thinking that such a condition doesn't normally slow us down. So 
I created a test case (skipping the map and all).

This worked, in that it built and seem to run ok. I'm not overly thrilled 
with the cast necessary to store the func pointer. Does anyone see a 
problem? Improvements?


Brian

========= code =========

#include <iostream>

#define CALL_HANDLER(object,ptrToMember)((object).*(ptrToMember))

class tbase
{
public:
   tbase() : p(0)
   {
   }
   typedef  int (tbase::*HandlerPtr)(int);
protected:
   HandlerPtr p;
};
class test : tbase
{
public:
   test()
   {
      p  = static_cast<HandlerPtr>(&test::f);
   }
   int f(int i)
   {
      std::cout << "f: " << i << "\n";
      return i;
   }
   void m()
   {
      CALL_HANDLER(*this, p)(1);
   }
};

int main()
{
   test t;
   t.m();
   return 0;
}

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Fun with member-function pointers "Default User" <defaultuserbr@yahoo.com> - 2011-08-22 16:41 -0500
  Re: Fun with member-function pointers Victor Bazarov <v.bazarov@comcast.invalid> - 2011-08-22 19:25 -0400
    Re: Fun with member-function pointers "Default User" <defaultuserbr@yahoo.com> - 2011-08-22 19:06 -0500
  Re: Fun with member-function pointers Juha Nieminen <nospam@thanks.invalid> - 2011-08-23 07:09 +0000
    Re: Fun with member-function pointers Victor Bazarov <v.bazarov@comcast.invalid> - 2011-08-23 08:04 -0400
      Re: Fun with member-function pointers Juha Nieminen <nospam@thanks.invalid> - 2011-08-23 13:34 +0000
        Re: Fun with member-function pointers Victor Bazarov <v.bazarov@comcast.invalid> - 2011-08-23 13:02 -0400
      Re: Fun with member-function pointers Andrey Tarasevich <andreytarasevich@hotmail.com> - 2011-08-23 19:12 -0700
    Re: Fun with member-function pointers Andrey Tarasevich <andreytarasevich@hotmail.com> - 2011-08-23 18:51 -0700
  Re: Fun with member-function pointers Marcel Müller <news.5.maazl@spamgourmet.com> - 2011-08-23 09:07 +0200
    Re: Fun with member-function pointers Juha Nieminen <nospam@thanks.invalid> - 2011-08-23 10:09 +0000
      Re: Fun with member-function pointers Marcel Müller <news.5.maazl@spamgourmet.com> - 2011-08-23 15:04 +0200
    Re: Fun with member-function pointers "Default User" <defaultuserbr@yahoo.com> - 2011-08-23 10:36 -0500
      Re: Fun with member-function pointers Andrey Tarasevich <andreytarasevich@hotmail.com> - 2011-08-23 18:46 -0700
        Re: Fun with member-function pointers "Default User" <defaultuserbr@yahoo.com> - 2011-08-24 09:33 -0500
          Re: Fun with member-function pointers Andrey Tarasevich <andreytarasevich@hotmail.com> - 2011-08-24 08:32 -0700
            Re: Fun with member-function pointers "Default User" <defaultuserbr@yahoo.com> - 2011-08-24 11:15 -0500
              Re: Fun with member-function pointers Andrey Tarasevich <andreytarasevich@hotmail.com> - 2011-08-24 09:30 -0700
      Re: Fun with member-function pointers Marcel Müller <news.5.maazl@spamgourmet.com> - 2011-08-24 12:27 +0200
        Re: Fun with member-function pointers Andrey Tarasevich <andreytarasevich@hotmail.com> - 2011-08-24 06:46 -0700
          Re: Fun with member-function pointers Marcel Müller <news.5.maazl@spamgourmet.org> - 2011-08-24 18:57 +0200
            Re: Fun with member-function pointers Paul <pchristor@yahoo.co.uk> - 2011-08-24 13:08 -0700
              Re: Fun with member-function pointers Andrey Tarasevich <andreytarasevich@hotmail.com> - 2011-08-24 13:44 -0700
                Re: Fun with member-function pointers Paul <pchristor@yahoo.co.uk> - 2011-08-25 04:23 -0700
                Re: Fun with member-function pointers Andrey Tarasevich <andreytarasevich@hotmail.com> - 2011-08-25 07:31 -0700
                Re: Fun with member-function pointers Andrey Tarasevich <andreytarasevich@hotmail.com> - 2011-08-25 08:21 -0700
                Re: Fun with member-function pointers Paul <pchristor@yahoo.co.uk> - 2011-08-25 10:50 -0700
                Re: Fun with member-function pointers Leigh Johnston <leigh@i42.co.uk> - 2011-08-25 13:57 +0100
                Re: Fun with member-function pointers Leigh Johnston <leigh@i42.co.uk> - 2011-08-25 14:08 +0100
                Re: Fun with member-function pointers Andrey Tarasevich <andreytarasevich@hotmail.com> - 2011-08-25 07:32 -0700
                Re: Fun with member-function pointers Leigh Johnston <leigh@i42.co.uk> - 2011-08-25 15:45 +0100
                Re: Fun with member-function pointers Andrey Tarasevich <andreytarasevich@hotmail.com> - 2011-08-25 07:48 -0700
    Re: Fun with member-function pointers Andrey Tarasevich <andreytarasevich@hotmail.com> - 2011-08-23 18:43 -0700
  Re: Fun with member-function pointers Paul <pchristor@yahoo.co.uk> - 2011-08-23 03:49 -0700
    Re: Fun with member-function pointers Paul <pchristor@yahoo.co.uk> - 2011-08-23 06:44 -0700
  Re: Fun with member-function pointers Andrey Tarasevich <andreytarasevich@hotmail.com> - 2011-08-23 18:28 -0700
  Re: Fun with member-function pointers Jeff Flinn <TriumphSprint2000@hotmail.com> - 2011-08-25 11:29 -0400

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