C++ with Interfaces
By Christopher Diggins, September 01, 2004
Christopher looks at how abstract base classes differ from interfaces and how you can implement efficient interfaces in C++ without virtual functions.
September, 2004: C++ with Interfaces
Example 1: Program output.
sizeof(IShape) = 8
timing 5000000 calls to IShape::MoveBy() ... time elapsed (msec): 187
sizeof(AbcShape&) = 16
timing 5000000 calls to AbcShape&::MoveBy() ... time elapsed (msec): 485
sizeof(IMoveable) = 8
timing 5000000 calls to IMoveable::MoveBy() ... time elapsed (msec): 203
sizeof(AbcMoveable&) = 4
timing 5000000 calls to AbcMoveable&::MoveBy() ... time elapsed (msec): 484
sizeof(Circle&) = 12
timing 5000000 calls to Circle&::MoveBy() ... time elapsed (msec): 156
sizeof(NaiveCircle&) = 28
timing 5000000 calls to NaiveCircle&::MoveBy() ... time elapsed (msec): 469
sizeof(Circle) = 12
timing 5000000 calls to Circle::MoveBy() ... time elapsed (msec): 79
sizeof(NaiveCircle) = 28
timing 5000000 calls to NaiveCircle::MoveBy() ... time elapsed (msec): 344
