python - Split List By Value and Keep Separators

Question

I have a list called list_of_strings that looks like this:

['a', 'b', 'c', 'a', 'd', 'c', 'e']

I want to split this list by a value (in this case c). I also want to keep c in the resulting split.

So the expected result is:

[['a', 'b', 'c'], ['a', 'd', 'c'], ['e']]]

Any easy way to do this?

Answer 1

You can use more_itertoools to accomplish this simply and clearly:

from more_itertools import split_after


lst = ["a", "b", "c", "a", "d", "c", "e"]
list(split_after(lst, lambda x: x == "c"))
# [['a', 'b', 'c'], ['a', 'd', 'c'], ['e']]

---

Another example, here we split words by simply changing the predicate:

lst = ["ant", "bat", "cat", "asp", "dog", "carp", "eel"]
list(split_after(lst, lambda x: x.startswith("c")))
# [['ant', 'bat', 'cat'], ['asp', 'dog', 'carp'], ['eel']]