RPL/2 4.0.0 pr 7

RPL/2 is a special language based on Lisp and Forth

RPL/2 is a special language, and could be the strange child of forbidden love between Lisp and Forth. The reversed polish notation and the definitional working come from Forth, only keeping an anonymous stack; the control structures come from Lisp. What a brilliant genealogy !

This language has very weak typing, if any typing at all. The variables are declared on-the-fly at their first use, and the type of the data to store at that time is used. So the same variable X might contain a complex matrix and a few moments later, a string.In fact, using variables is not very common, because everything can be done directly with objects present in the stack.