[Tutor] help

[Danny Yoo]

On Tue, 2 Oct 2001, RIDDLE BOX wrote:

> I may have the been trying to do this wrong with that code, but I
> would like the program to look at a file and then when you are done
> looking at that file, I would like it to ask if you would like to look
> at another file, and keep asking that until you quit the program. this
> is my whole code right now. I hope I am on the right track.  thanks
> for all your help I am pretty sure that my while statement is wrong
> but I dont know how to get it to work thanks

Here's a small example of doing something until the user types the word
"quit".

###
while 1:
    filename = raw_input("What file? ('quit' to quit)")
    if filename == 'quit':
        break
    inp = open(filename)
    for line in inp.readlines():
        print line
###

What might seem unusual about this code is that it is an infinite loop!  
Or, at least, it seems that way.  There is one way out of the loop though:
if the user types 'quit' when asked for a filename, we can "break" out of
the loop.



We can write this another way:

###
filename = raw_input("What file? ('quit' to quit)")
while filename != 'quit':
    inp = open(filename)
    for line in inp.readlines():
        print line
    filename = raw_input("What file? ('quit' to quit)")
###


In this case, we're rearranging some of the statements, but the effect is
the same --- or, at least, should be the same.  I haven't tested this code
out at all yet.  *grin*

Try some while loops of your own; if you find that a while loop has gone
out of control, you can press the key combination "Control-c", and that
usually cancels a Python program.


Good luck!