input vs. raw_input: Python Interactive Shell Application?

Question

I was working off of the answer in this question: Python Interactive Shell Type Application

My code looks like this

def main():
  while True:
    s =         


        

Answer 1

You're running it under Python 2.x, where input() actually evaluates what you type as a Python expression. Thus, it's looking for a variable named hello, and, since you haven't defined one, it throws the error. Either use Python 3.x, or use raw_input().

From the parentheses in your print I assume you intended to run it under Python 3.x.

Answer 2

if s == 'hello':
  print('hi')

elif s == 'exit':
  break

else:
  print('Undefined input')

This should take care of undefined user input.