[BroZeus]

There is really no way to detect it you need to pass the format of argument like in functions like mysql_tquery, where you pass the format of variable to be passed to callback as a string.
tagof doesn't works with getarg directly it gives error.
For example:

PHP код:

tagof(getarg(0)); // gives error won't compile 


So best option is to make your function something like

PHP код:

//example call to function someFunction("dfd", 3, 45, 55.5, 8)
stock someFunction(args[],  s = sizeof(args), ...)
{
     for(new i = 0; i < s; i++)
     {
         switch(getarg(0, i))
         {
             case 'd':{ /* interger */ }
             case 'f':{ /* float */ }
             //so on
         }
     }
}