[Tutor] A little math and Python: rpn - my last one

[Gregor Lingl]

my last version, this time a practical calculator:

 >>> def rpn():
        stack=[]
        while 1:
            item = raw_input("> ")
            if item in ["+","-","*","/"]:
                res=str(eval(stack[-2]+item+stack[-1]))
                print res
                stack[-2:]=[res]
            elif item == "":
                break
            else:
                stack.append(item)
           
 >>> rpn()
 > 3
 > 4
 > +
7
 > 6
 > +
13
 > 12
 > *
156
 > 6
 > /
26.0
 >
 >>>

Thanks for your patience
Gregor

P.S.: Do you still think, Danny was right, when he wrote

It might make an interesting project to write an RPN calculator in Python.