Factory methods, also called the named constructor idiom, are basically member functions that call a private constructor for you. When do we use them? Here are a few scenarios:
- When there are many different ways to construct an object, which would make errors likely. For example, imagine constructing a class for storing different color channels for a given pixel; each channel is represented by a one-byte value. Using just a constructor would make it too easy to pass the wrong order of channels, or values meant for a different color palette entirely. Also, switching the pixel's internal representation of colors would get tricky pretty fast. You could argue that we should have different types representing colors in those different formats, but often, using a factory method is a valid approach as well.
- When you want to force the object to be created on the heap or in another specific memory area. If your object takes up loads of space on the stack and you&apos...
