Extensions

Back in the early 90s, when the primary language that I developed in was C, I had numerous custom libraries that contained functionality that was not a part of the standard C library. I found these libraries extremely useful because I tended to use the functionality they provided in most of my projects. This functionality included things such as converting the first letter of a character array to uppercase, or converting a numerical value to a currency string (two digits after the decimal point and a currency symbol). Having libraries such as these is extremely useful because there is always a functionality that we find useful that is not included in the standard library of the language we are developing in. I usually implemented this extra functionality in C with global functions. In more modern object-oriented languages, we can implement this functionality by subclassing...