expr-calc is a simple program that I developed during an introductory C++ course. Do not expect anything advanced and fancy. The calculator does not support command line arguments and any kind of interaction in general. As is, it probably does not have any practical usability at all. Nevertheless, I have decided to publish it because it exposes some nice C++ features. For instance, it demonstrates how to:

• Split code into header and source files
• Use namespaces properly (avoid the lazy and dangerous using namespace std syntax)
• Create interfaces using pure virtual methods
• Use class inheritance to facilitate code sharing
• Create simple makefiles for making project compilation fast and easy