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Python

Posted by spencer tintorri
spencer tintorri
6,184 Points

Except block runs. Then what? Code above the Try block runs?

while tickets_remaining >= 1:
    print("There are {} tickets remaining!".format(tickets_remaining))
    name = input("Hey there, what is your name, fam?   ")
    # ValueError - handle if they dont input a number
    try:        
        tickets_requested = int(input("How many tickets would you like, {}?   ".format(name)))
        # Raise ValueError if tickets_requested > tickets_remaining
    except ValueError:
        # Include the error text in the output
        print("Oh no! That's not a valid value. Put in a number, dumb dumb.")
    else:
        total_cost = tickets_requested * TICKET_PRICE
        print("The total cost of {} tickets is ${}.".format(tickets_requested, total_cost))
        proceed = input("{}, would you like to complete your purchase of {} tickets? Y or N?   ".format(name, tickets_requested))

In this example, answering "How many tickets would you like?" with a non-integer runs this

Oh no! That's not a valid value. Put in a number, dumb dumb.
There are 100 tickets remaining!
Hey there, what is your name, fam?

I thought the beginning of the Try block is supposed to run after the Except block runs. Or am I misunderstanding something?

1 Answer

Alex Koumparos
.a{fill-rule:evenodd;}techdegree
Alex Koumparos
Python Development Techdegree Student 36,888 Points

Hi Spencer,

The sequence with try/except/else is as follows:

First, attempt to execute the code inside the try block;

Next, if the try code succeeds, execute the else block (then continue executing the code after the try/except/else);

Otherwise, if the try code failed with the specified exception, execute the corresponding except block (then continue executing the code after the try/except/else);

Otherwise, if the try code failed with a non-specified exception, crash.

Since you have no code inside your while loop after the try/except/else sequence, the next line after the sequence is to go back to the first line in the while loop.

Hope that clears things up for you.

Cheers

Alex