WSBasic is a BASIC interpreter written entirely in C++ without the use
of lex or yacc.  It shows how one can create a compiler or interpreter
using some simple classes to parse and/or execute script code.  It is
a good way to fully understand how a parser/compiler actually works,
at least that was the original purpose of this project.  Later the
ability to run shell commands was added just like in bash scripting
and this gives the project also some nice practical use.