Just curious to know if anyone knows of an inbuilt version of:
bool_list: List[bool] = # some non-empty list of booleans
result = all(bool_list) or not any(bool_list)
# What I'm looking for
result = allsame(bool_list)
Asked
Active
Viewed 42 times
2
Alexander Soare
- 2,825
- 3
- 25
- 53
-
3Do you mean like `len(set(bool_list)) == 1`? – thefourtheye Sep 21 '22 at 10:53
-
@thefourtheye beautiful. I mean it's still a step above inbuilt but it saves me creating an intermediate variable if my bool_list is generated via list comprehension or some other non-trivial expression. – Alexander Soare Sep 21 '22 at 10:53
-
3Nothing inbuilt but several ways to write it concisely. – Michael Butscher Sep 21 '22 at 10:55
-
3Relevant: https://stackoverflow.com/q/3844801/1903116 – thefourtheye Sep 21 '22 at 11:01
-
@thefourtheye That fails if the list is empty. Also, likely inefficient. – Kelly Bundy Sep 21 '22 at 11:47
1 Answers
1
Not a built-in but does exactly what you are looking for in an efficient way:
from itertools recipes:
def all_equal(iterable):
"Returns True if all the elements are equal to each other"
g = groupby(iterable)
return next(g, True) and not next(g, False)
Gábor Fekete
- 1,343
- 8
- 16
-
-
The groupby will create a generator, so this will return at the first mismatch and not iterate further. – Gábor Fekete Sep 21 '22 at 13:36
-
True (except it's not a generator but an iterator), but I don't see why you're saying that. – Kelly Bundy Sep 21 '22 at 13:44