exit to interpreter?

[belinda thom]

Hi,

I'm writing a function that polls the user for keyboard input,  
looping until it has determined that the user has entered a valid  
string of characters, in which case it returns that string so it can  
be processed up the call stack. My problem is this. I'd also like it  
to handle a special string (e.g. 'quit'), in which case control  
should return to the Python command line as opposed to returning the  
string up the call stack.

sys.exit seemed like a good choice, but it exits the python interpreter.

I could use an exception for this purpose, but was wondering if  
there's a better way?

--b