为什么我在索引字典时会收到“字符串索引必须是整数”错误？

Question

I am trying to code a python console game framework. How I have designed it, there is a dictionary called game_state which is updated by a function passed into the loop function. After one iteration of the loop, it gives the error "String indices must be integers." The stack trace shows that the error is occuring at the line if game_state["running"] == false . When printing out game_state, it seems to be an empty string. Why is this happening, and what can I do to fix it?

def run_loop(calculate, draw, initial_state):
  fd = sys.stdin.fileno()
  old_settings = termios.tcgetattr(fd)
  tty.setraw(sys.stdin)
  game_state = initial_state
  with raw(sys.stdin):
    with nonblocking(sys.stdin):
      try:
        while True:
            try:
                c = sys.stdin.read(1)
                game_state = calculate(c, game_state)
                print_map(draw(game_state))
                if game_state["running"] == False:
                  break
            except IOError:
                print('not ready')
          
            time.sleep(.1)
      finally:
        termios.tcsetattr(fd, termios.TCSADRAIN, old_settings)
  
def game(state, press):
  mut_state = state
  if press == "q":
    mut_state["running"] = False
  return mut_state
def display(game_state):
  return [["Yay!"]]
run_loop(game, display, {"running": True})

Answer 1

The answer was right in front of me. I was passing in the input first, meaning that empty input was overwriting the game state. It should have been calculate(game_state, c) .