### Example of Defining an APP Parameterized Manipulator

In the following example, the macro IOMANIPdeclare is called with the user-defined class my_class as an argument. One of the classes that is produced, OAPP(my_class), is used to define the manipulator pre_print.

    //   Creating and using parameterized manipulators

    #include <iomanip.h>

    // declare class

    class my_class {
       public:
          char * s1;
          const char c;
          unsigned short ctr;
          my_class(char *theme, const char suffix,
               unsigned short times):
               s1(theme), c(suffix), ctr(times) {}
       };

    // print a character an indicated number of times
    // followed by a string

    ostream& produce_prefix(ostream& o, my_class mc) {
       for (register i=mc.ctr; i; --i) o << mc.c ;
       o << mc.s1;
       return o;
    }

    IOMANIPdeclare(my_class);

    // define a manipulator for the class my_class
    OAPP(my_class) pre_print=produce_prefix;

    void main() {
       my_class obj("Hello",'-',10);
       cout << pre_print(obj) << endl;
    }

This program produces the following output:

    ----------Hello