Mega Code Archive
A better way to overload !, , and & for TwoDimension
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This version automatically enables the && and || operators.
using System;
class TwoDimension {
int x, y;
public TwoDimension() {
x = y = 0;
}
public TwoDimension(int i, int j) {
x = i;
y = j;
}
// Overload | for short-circuit evaluation.
public static TwoDimension operator |(TwoDimension op1, TwoDimension op2)
{
if( ((op1.x != 0) || (op1.y != 0) ) |
((op2.x != 0) || (op2.y != 0)) )
return new TwoDimension(1, 1);
else
return new TwoDimension(0, 0);
}
// Overload & for short-circuit evaluation.
public static TwoDimension operator &(TwoDimension op1, TwoDimension op2)
{
if( ((op1.x != 0) && (op1.y != 0)) &
((op2.x != 0) && (op2.y != 0) ) )
return new TwoDimension(1, 1);
else
return new TwoDimension(0, 0);
}
// Overload !.
public static bool operator !(TwoDimension op)
{
if(op) return false;
else return true;
}
// Overload true.
public static bool operator true(TwoDimension op) {
if((op.x != 0) || (op.y != 0))
return true; // at least one coordinate is non-zero
else
return false;
}
// Overload false.
public static bool operator false(TwoDimension op) {
if((op.x == 0) && (op.y == 0))
return true; // all coordinates are zero
else
return false;
}
// Show X, Y
public void show()
{
Console.WriteLine(x + ", " + y);
}
}
class MainClass {
public static void Main() {
TwoDimension a = new TwoDimension(5, 6);
TwoDimension b = new TwoDimension(10, 10);
TwoDimension c = new TwoDimension(0, 0);
Console.Write("Here is a: ");
a.show();
Console.Write("Here is b: ");
b.show();
Console.Write("Here is c: ");
c.show();
Console.WriteLine();
if(a) {
Console.WriteLine("a is true.");
}
if(b) {
Console.WriteLine("b is true.");
}
if(c) {
Console.WriteLine("c is true.");
}
if(!a) {
Console.WriteLine("a is false.");
}
if(!b) {
Console.WriteLine("b is false.");
}
if(!c) {
Console.WriteLine("c is false.");
}
Console.WriteLine();
Console.WriteLine("Use & and |");
if(a & b)
Console.WriteLine("a & b is true.");
else
Console.WriteLine("a & b is false.");
if(a & c)
Console.WriteLine("a & c is true.");
else
Console.WriteLine("a & c is false.");
if(a | b)
Console.WriteLine("a | b is true.");
else
Console.WriteLine("a | b is false.");
if(a | c)
Console.WriteLine("a | c is true.");
else
Console.WriteLine("a | c is false.");
Console.WriteLine();
// now use short-circuit ops
Console.WriteLine("Use short-circuit && and ||");
if(a && b)
Console.WriteLine("a && b is true.");
else
Console.WriteLine("a && b is false.");
if(a && c)
Console.WriteLine("a && c is true.");
else
Console.WriteLine("a && c is false.");
if(a || b)
Console.WriteLine("a || b is true.");
else
Console.WriteLine("a || b is false.");
if(a || c)
Console.WriteLine("a || c is true.");
else
Console.WriteLine("a || c is false.");
}
}
Here is a: 5, 6
Here is b: 10, 10
Here is c: 0, 0
a is true.
b is true.
c is false.
Use & and |
a & b is true.
a & c is false.
a | b is true.
a | c is true.
Use short-circuit && and ||
a && b is true.
a && c is false.
a || b is true.
a || c is true.
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