Can't understand scope error.

This is the place for queries that don't fit in any of the other categories.

Can't understand scope error.

Postby Hypernova » Tue Jun 25, 2013 10:30 am

For some reason, when I run this code(an exercise for learning python on this site: ), the error says that using [location] for the indices in the list: prog, cannot be done because [location] isn't an integer. But it is defined as an integer above: location = 0.

So is the while loop beyond the scope of the original value of location?

prog- is a list of strings.
The print statement is just for me trying to debug.
The if statement looks for a condition to end the loop.

Code: Select all
# here is a broken solution to get you started
def execute(prog):
   location = 0
   while True:
      if location==len(prog)-1:
         return "success"
      location = findLine(prog, T)

Traceback (most recent call last):
  In line 8 of the code you submitted:
TypeError: list indices must be integers, not NoneType

As a small aside, it looks as if the original definition of location is used as a way to refer to list index 0, but then the value of location is updated by location=findLine(prog,T). Which to me, seems to make the use of location as a counter pointless in the way it's used.

Any help or discussion about this will be great. Many thanks.
Posts: 18
Joined: Mon Jun 10, 2013 12:23 am

Re: Can't understand scope error.

Postby micseydel » Tue Jun 25, 2013 11:18 am

findLine() is return a non-integer value. I suggest you always post all the code, and don't try to summarize the traceback as you did. Tracebacks are great, and if you provide all the code we can give a very precise answer or explanation.
Due to the reasons discussed here we will be moving to on October 1, 2016.

This forum will be locked down and no one will be able to post/edit/create threads, etc. here from thereafter. Please create an account at the new site to continue discussion.
User avatar
Posts: 2995
Joined: Tue Feb 12, 2013 2:18 am
Location: Mountain View, CA

Re: Can't understand scope error.

Postby Hypernova » Thu Jun 27, 2013 9:47 am

Hi micseydel, thanks for the tip. I realized what was happening thanks to you informing me of the real nature of the error. Sorry about the broken code, the code was broken up into separate exercises and I didn't think to add the separate pieces of code.
Posts: 18
Joined: Mon Jun 10, 2013 12:23 am

Return to General Coding Help

Who is online

Users browsing this forum: No registered users and 12 guests