Fix Python – I want to exception handle ‘list index out of range.’

Question

Asked By – H.Choi

I am using BeautifulSoup and parsing some HTMLs.

I’m getting a certain data from each HTML (using for loop) and adding that data to a certain list.

The problem is, some of the HTMLs have different format (and they don’t have the data that I want in them).

So, I was trying to use exception handling and add value null to the list (I should do this since the sequence of data is important.)

For instance, I have a code like:

soup = BeautifulSoup(links)
dlist = soup.findAll('dd', 'title')
# I'm trying to find content between <dd class='title'> and </dd>
gotdata = dlist[1]
# and what i want is the 2nd content of those
newlist.append(gotdata)
# and I add that to a newlist

and some of the links don’t have any <dd class='title'>, so what I want to do is add string null to the list instead.

The error appears:

list index out of range.

What I have done tried is to add some lines like this:

if not dlist[1]:  
   newlist.append('null')
   continue

But it doesn’t work out. It still shows error:

list index out of range.

What should I do about this? Should I use exception handling? or is there any easier way?

Any suggestions? Any help would be really great!

Now we will see solution for issue: I want to exception handle ‘list index out of range.’


Answer

Handling the exception is the way to go:

try:
    gotdata = dlist[1]
except IndexError:
    gotdata = 'null'

Of course you could also check the len() of dlist; but handling the exception is more intuitive.

This question is answered By – ThiefMaster

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