The use of assertions is the single most important thing you can do to validate your code during development, while at the same time leaving an executable documentation trail in your code that reveals what you were thinking when you wrote the code in the first place. Before you let your code out of your hands it should be rigorously tested. A framework for automated unit testing is an indispensable tool for successful, everyday software development.

Part 2: The Standard C++ Library

3. Strings in Depth. Text processing is the most common programming activity by far. The C++ string class relieves the programmer from memory management issues, while at the same time delivering a powerhouse of text processing capability. C++ also supports the use of wide characters and locales for internationalized applications.

 4. Iostreams. One of the original C++ libraries—the one that provides the essential I/O facility—is called iostreams. Iostreams is intended to replace C’s stdio.h with an I/O library that is easier to use, more flexible, and extensible—you can adapt it to work with your new classes. This chapter teaches you the ins and outs of how to make the best use of the existing iostream library for standard I/O, file I/O, and in-memory formatting^.

5. Templates in Depth. The distinguishing feature of «modern C++» is the broad power of templates. Templates are for more than just generic containers; they support development of robust, generic, high-performance libraries. There is a lot to know about templates—they constitute, as it were, a sub-language within the C++ language, and give the programmer an impressive degree of control over the compilation process. It is not an understatement to say that templates have revolutionized C++ programming.