JezK
Edit File: _loop.py
from typing import Iterable, Tuple, TypeVar T = TypeVar("T") def loop_first(values: Iterable[T]) -> Iterable[Tuple[bool, T]]: """Iterate and generate a tuple with a flag for first value.""" iter_values = iter(values) try: value = next(iter_values) except StopIteration: return yield True, value for value in iter_values: yield False, value def loop_last(values: Iterable[T]) -> Iterable[Tuple[bool, T]]: """Iterate and generate a tuple with a flag for last value.""" iter_values = iter(values) try: previous_value = next(iter_values) except StopIteration: return for value in iter_values: yield False, previous_value previous_value = value yield True, previous_value def loop_first_last(values: Iterable[T]) -> Iterable[Tuple[bool, bool, T]]: """Iterate and generate a tuple with a flag for first and last value.""" iter_values = iter(values) try: previous_value = next(iter_values) except StopIteration: return first = True for value in iter_values: yield first, False, previous_value first = False previous_value = value yield first, True, previous_value