defensive-programming

What is a copy constructor ? Can someone share a small example that can be helpful to understand along with defensive copying principle ? Here's a good example: class Point { final int x; final int y; Point(int x, int y) { this.x = x; this.y = y; } Point(Point p) { this(p.x, p.y); } } Note how the constructor Point(Point p) takes a Point and makes a copy of it - that's a copy constructor . This is a defensive copy because the original Point is protected from change by taking a copy of it. So now: // A simple point. Point p1 = new Point(3,42); // A new point at the same place as p1 but a

I've been a professional software engineer for about a year now, having graduated with a CS degree. I've known about assertions for a while in C++ and C, but had no idea they existed in C# and .NET at all until recently. Our production code contains no asserts whatsoever and my question is this... Should I begin using Asserts in our production code? And if so, When is its use most appropriate? Would it make more sense to do Debug.Assert(val != null); or if ( val == null ) throw new exception(); In Debugging Microsoft .NET 2.0 Applications John Robbins has a big section on assertions. His main

I'm reading some lecture notes of my C++ lecturer and he wrote the following: Use Indentation // OK Never rely on operator precedence - Always use parentheses // OK Always use a { } block - even for a single line // not OK , why ??? Const object on left side of comparison // OK Use unsigned for variables that are >= 0 // nice trick Set Pointer to NULL after deletion - Double delete protection // not bad The 3rd technique is not clear to me: what would I gain by placing one line in a { ... } ? For example, take this weird code: int j = 0; for (int i = 0 ; i < 100 ; ++i) { if (i % 2 == 0) { j++;