c++ varargs/variadic function with two types of arguments -

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i trying implement variadic function. searched web , ended finding out examples handle 1 type of arguments (for example calculating average of many integers). im case argument type not fixed. can either involve char*, int or both @ same time. here code ended :

void insertinto(int dummy, ... ) {    int = dummy;    va_list marker;    va_start( marker, dummy );     /* initialize variable arguments. */    while( != -1 ) {       cout<<"arg "<<i<<endl;              /* or c here */       = va_arg( marker, int);       //c = va_arg( marker, char*);    }    va_end( marker );              /* reset variable arguments.      */

now work okay if had deal integers see have char* c variable in comments use in case argument char*.

so question is, how handle returned value of va_arg without knowing if int or char* ?

since you're doing c++ there's no need use untyped c-style variadic function.

you can define chainable method like

  class inserter   {   public:       inserter& operator()( char const* s )       {           cout << s << endl;           return *this;       }        inserter& operator()( int )       {           cout << << endl;           return *this;       }   };

then use like

inserter()( "blah" )( 42 )( "duh" )

variant templated insert operation commonly used building strings.

cheers & hth.,


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