Intro

Though more-itertools contains many functions, it can never be 'complete'.

Below extensions were or could be proposed, but not (yet) added to more-itertools. Module more-more-itertools acts as their abode until they get added to more-itertools.

Functions

Logic

lazy_product

Lazely iterate over product of *iterables (potentially with repeat), which can be unbounded, differentiating lazy_product from stdlib itertool.product.

• Still #TODO

diagonal_lazy_product

Lazely iterate over product of *iterables (potentially with repeat), which can be unbounded, in a 'diagonal' fashion.

• Still #TODO

Count

at_least_n

at_least_n(iterable, /, n, *, too_short=None)

Iterate over iterable and validate it has at least n items.

If it has fewer than n items, call function too_short with its item-count.

• Suggested for addition to more-itertools as #1053 on 9 Aug 2025.

at_most_n

at_most_n(iterable, /, n, *, too_long=None)

Iterate over the first ≤n items of iterable and validate it has at most n items (i.e. is exhausted then).

If it has more than n items, call function too_long with the number n + 1. Even if too_long doesn't raise, the remaining items (>n) get skipped.

• Suggested for addition to more-itertools as #1053 on 9 Aug 2025.

Time

throttle

throttle(iterable, /, *, min_step) or throttle(iterable, /, *, max_rate)

Iterate over iterable at (potentially slowed-down) pace of at least min_step sec per item, or at most max_rate items per sec.

timeout

timeout(iterable, /, max_time, *, exception=TimeoutError)

Iterate over iterable with potential premature stop after a timeout of max_time sec. If iterable takes longer than max_time sec, i.e. a timeout occurs, exception is raised if not None. For a timeout with exception None, iteration stops without exception (cf. itertools.islice(), but after certain duration instead of certain count).