Libraries, Frameworks & API's

Using libraries is critical for effective code reuse and limiting the amount of reinventing that can take place.

Libraries can be packaged in 3 different ways in C++:

1. Open source package => the full source is made a available
2. Dev package => contains a lib with the header files and not the full source
3. Runtime library => only a compiled .dll and no corresponding source files

Libraries are typically inluded into the header file and class declaration as follows:

#include <square.h>
#include <Square>

The linker also needs to be configured for any external packages that need to be brought in but its beyond the scope of the course.

Frameworks are typically large collection of general-purpose or domain specific classes and conventions designed to improve the consistency and ease of design for example the web package for PHP, Laravel.

They typically include a well documented API and implement recommend design patterns throughout. Design patterns do change over time so its not a silver bullet.

API's are a description of the public functions, classes and interfaces in a library in the context of C++.