Get string from list if that string contains substring

Question

Lets say I have following data:

l = ['abc', 'def', 'ghi']
sub = 'bc'

'bc' will allways be a substring for only one element in the list!

and a function that works like this:

def f(l, sub):
    return [x for x in l if sub in x][0]

So the function will return 'abc' because it has 'bc' in it

My Question is: What is the other way to write that function so it doesn't use list index? ([0]) Is there a way to do this any 'prettier'?

If you need only first occurrence, just loop through `l` and return element when you find it. `def f(l, sub): for x in l: if sub in x: return x` — Yevhen Kuzmovych, Nov 28 '19 at 14:08

score 8 · Accepted Answer · answered Nov 28 '19 at 14:08

8

Use next(..) with a generator. This will sort of break the moment it finds the first instance. Of course, this is assuming one element definitely exists in your list.

def f(l, sub):
    return next(x for x in l if sub in x)

answered Nov 28 '19 at 14:08

UltraInstinct

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score 4 · Answer 2 · answered Nov 28 '19 at 14:08

4

Very simple:

next(x for x in l if sub in x)

In this way you don't create the entire list.

answered Nov 28 '19 at 14:08

Riccardo Bucco

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score 0 · Answer 3 · answered Nov 28 '19 at 14:08

0

next(x for x in iter(l) if sub in x)

answered Nov 28 '19 at 14:08

Raymond Reddington

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Get string from list if that string contains substring

3 Answers3