python nested list and string trimming in a for statement-CodePudding

Now, having a list of lists with 2 strings:

l1 = [['a', 'www.apple.com/a www.google.com www.yahoo.com'],
    ['b', 'www.apple.com/sm www.sashgh.com www.uensg.com'],
    ['c', 'www.apple.com/oths www.zhiut.com'],
    ['d', 'www.amazon.com www.toronto.com']]

I want to keep the first string, and get the 'apple.com' url in the 2nd string or if there is not 'apple.com' give a None (like the case in 'd'):

l2 = [['a', 'www.apple.com/a'], 
    ['b', 'www.apple.com/sm'],
    ['c', 'www.apple.com/oths'],
    ['d', None]]

I tried this :

l2 = []
for l in l1:
    for url in l[1].split(' '):
        if 'apple.com' in url:
            l2.append([l[0], url])
            break
        else:
            l2.append([l[0], None])
            break

and the code now worked!

CodePudding user response：

Since you're only appending the first apple.com in the split strings in the second elements of the sublists, you could use next and a generator expression to extract the first apple.coms.

out = [[first, next((s for s in second.split() if 'apple.com' in s), None)] for first, second in l1]

Output:

[['a', 'www.apple.com/a'],
 ['b', 'www.apple.com/sm'],
 ['c', 'www.apple.com/oths'],
 ['d', None]]