PLEASE NOTE: This is NOT about the use of eval(), it is about the potential quality (or lack thereof) of a book it is used and taught in. SO already has countless threads ab
Well, to combine eval() and input() in such a way creates a rudimentary but possibly very harmful 'shell'.
I haven't read the book, but I'd take it with a grain of salt. It's not just bad practice, it implements one deadly combo of functions.