mirror of
https://github.com/python/cpython.git
synced 2025-08-01 15:43:13 +00:00
d5cd2effa6
* bpo-45514: Apply changes from importlib_resources@a3ef4128c6 * Mark legacy functions as deprecated in the docs and link to the migration docs in importlib_resources docs. * Apply changes from importlib_resources@329ae9d5f2c. * Indicate importlib.resources as a module. Co-authored-by: Filipe Laíns <lains@riseup.net>
35 lines
884 B
Python
35 lines
884 B
Python
from itertools import filterfalse
|
|
|
|
from typing import (
|
|
Callable,
|
|
Iterable,
|
|
Iterator,
|
|
Optional,
|
|
Set,
|
|
TypeVar,
|
|
Union,
|
|
)
|
|
|
|
# Type and type variable definitions
|
|
_T = TypeVar('_T')
|
|
_U = TypeVar('_U')
|
|
|
|
|
|
def unique_everseen(
|
|
iterable: Iterable[_T], key: Optional[Callable[[_T], _U]] = None
|
|
) -> Iterator[_T]:
|
|
"List unique elements, preserving order. Remember all elements ever seen."
|
|
# unique_everseen('AAAABBBCCDAABBB') --> A B C D
|
|
# unique_everseen('ABBCcAD', str.lower) --> A B C D
|
|
seen: Set[Union[_T, _U]] = set()
|
|
seen_add = seen.add
|
|
if key is None:
|
|
for element in filterfalse(seen.__contains__, iterable):
|
|
seen_add(element)
|
|
yield element
|
|
else:
|
|
for element in iterable:
|
|
k = key(element)
|
|
if k not in seen:
|
|
seen_add(k)
|
|
yield element
|