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python - try block inside while statement

I'm just starting out with Python 2.7 and I don't understand why something is happening:

In the following code, an embellished version of an example from the python 2.7.2 tutorial, I get an unexpected result:

while True:
    try:
        x = int(raw_input("Please enter a number: "))
        break
    except ValueError:
        print "Oops!  That was not a valid number.  Try again..."
    else:
        print 'Thanks,',x,'is indeed an integer'
    finally:
        print 'all done, bye'

When I put in an integer, the code ignores the else: statement and cuts straight to finally:. Clearly it's something to do with the while True: at the top but why is it happening?

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1 Answer

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by (71.8m points)

The break statement is pulling out of the loop, so the else statement will never be reached.

Put the break in the else clause instead, like so:

while True:
    try:
        x = int(raw_input("Please enter a number: "))
    except ValueError:
        print "Oops!  That was not a valid number.  Try again..."
    else:
        print 'Thanks,',x,'is indeed an integer'
        break

print 'all done, bye'

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