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How to silence "unused parameter" warnings
==========================================

   "When I use `-Wall' (or `-Wunused'), g++ warns about unused
parameters.  But the parameters have to be there, for use in derived
class functions.  How do I get g++ to stop complaining?"

   The answer is to simply omit the names of the unused parameters when
defining the function.  This makes clear, both to g++ and to readers of
your code, that the parameter is unused.  For example:

     int Foo::bar(int arg) { return 0; }

   will give a warning for the unused parameter `arg'.  To suppress the
warning write

     int Foo::bar(int) { return 0; }