Caterpillar

Languages that predominantly employ postfix operators, use a stack-based evaluation model. I talked about this yesterday. To the best of my knowledge, this stack-based model is inherent to postfix operators. At least I can't come up with an alternative, nor can I find examples of languages that use postfix notation, but no stack.

What I find surprising though, is how closely these languages adhere to the stack-based model. Languages that emphasize prefix and infix operators are not completely based around, and allow direct manipulation of, their respective model (although that sounds like an interesting experiment).

But languages that focus on postfix operators often display a particular purity. Other means of defining data flow, like named variables, are either strongly discouraged or not part of the language at all. And I think this might be to their detriment. Employing postfix operators within a more traditional structure, with expressions, statements, and variables, is possibly a better direction.