Question

How can I force python to ignore IndexError without using try & except every single value that I am extracting?

My XML have multiple values that needed to be extracted. Some records don’t have the value / at root[0], so I have to manually use try & except IndexError: for every single node that I am extracting.

Here’s my code:

try:
    a = etree.XPath('/Data/a/b/nodeA/text()')(root)[0]  
except IndexError:  
    a = ''
try:
    b = etree.XPath('/Data/a/b/x/y/nodeB/text()')(root)[0]  
except IndexError:  
    b = ''
try:
    c = etree.XPath('/Data/a/b/d/nodeB/text()')(root)[0]  
except IndexError:  
    c = ''

Answer 1

When I use xpath queries I try to use looping instead of indexing. That way if the query doesn’t find anything, the code nested in the loop never runs and you don’
t have to index because the loop values get bound to a local name in each iteration. Permit an example.

for a, b, c in zip(
    etree.XPath('/Data/a/b/nodeA/text()')
    etree.XPath('/Data/a/b/x/y/nodeB/text()')
    etree.XPath('/Data/a/b/d/nodeB/text()')):

    print a, b, c