_TOWARDS A LESS OBJECT-ORIENTED VIEW OF C++_
by Harris Shiffman


Example 1: When subscript are within range, the subscript operator 
invokes the one it inherits 


int& protected_array::operator[] (int x)
{ return (x >= 0 && x < size()) ?
    array::operator[] (x) : error_value; }



Example 2: Defining two functions for finding the smaller of a pair of numbers


    int min (int a, int b)
    { return a < b ? a : b; }

    double min (double a, double b)
    { return a < b ? a : b; }

    main ()
    { int x = min (5, 7);
      double y = min (3.2, 1.3);
      double z = min (16.3, 2); }

    % CC min.cc

   "min.cc", line 10: error: ambiguous call: min ( double , int )
    "min.cc", line 10: choice of min()s:
    "min.cc", line 10:        int min(int , int );
    "min.cc", line 10:        double min(double , double );
    Compilation failed
    % 



Example 3: (a) Overloading of function names and basic operators like 
plus (+) and equals (=) make it possible for programs to treat these data 
types as if they were built into the language; (b) The template facility 
makes it possible to write general container classes which can be 
instantiated to hold any particular kind of value. 

(a)
    #include <stream.h>
    #include "fraction.h"
    #include "string.h"

    main ()
    { Fraction d = .5, e(2, 3);
      Fraction f = d + e - 1;
      cout << "F is " << f << endl;     // Prints "F is 1/6"

      String g = "Hello,", h = " there";
      String i = g + h;
      cout << "I is " << i << endl; }      // Prints "I is Hello, there"

(b)

     #include <stream.h>
     #include "stack.h"

     main ()
     { stack<double> s1;      // Create a stack of doubles
       for (int i = 0; i < 10; i++)
         s1.push (i + .5);

       for (i = 0; i < 5; i++)
         cout << s1.pop() << " " << s1 << endl;

       stack<char*> s2;       // Create a stack of character pointers
       s2.push ("abc");
       s2.push ("def");
       s2.push ("ghi");

       while (!s2.is_empty())
         cout << s2.pop() << " " << s2 << endl; }