[issue40806] itertools.product not lazy

Raymond Hettinger added the comment: New changeset e4cc3a7c1f5ba9ea2c3015a5bf09cb5b93db5d47 by Miss Islington (bot) in branch '3.9': bpo-40806: itertools.product immediately consumes its inputs (GH-20492) (GH-20498) https://github.com/python/cpython/commit/e4cc3a7c1f5ba9ea2c3015a5bf09cb5b93d

[issue40806] itertools.product not lazy

Raymond Hettinger added the comment: Updated the docs to note that inputs are fully consumed before the iterator is run. FYI, notes on infinite iterable inputs likely belong the FAQs because they aren't specific to product(). Similar effects would be seen with list(x(1)), sorted(x(1)), set

[issue40806] itertools.product not lazy

Raymond Hettinger added the comment: New changeset cfc6ce4d40f2f01314b7e283fb972a7bb3ed3faa by Ramil Nugmanov in branch 'master': bpo-40806: Clarify that itertools.product immediately consumes its inpt (GH-20492) https://github.com/python/cpython/commit/cfc6ce4d40f2f01314b7e283fb972a7bb3ed3f

[issue40806] itertools.product not lazy

Change by miss-islington : -- nosy: +miss-islington nosy_count: 4.0 -> 5.0 pull_requests: +19747 pull_request: https://github.com/python/cpython/pull/20498 ___ Python tracker _

[issue40806] itertools.product not lazy

Change by Raymond Hettinger : -- assignee: -> rhettinger ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe: htt

[issue40806] itertools.product not lazy

Change by Ramil Nugmanov : -- keywords: +patch pull_requests: +19741 stage: -> patch review pull_request: https://github.com/python/cpython/pull/20492 ___ Python tracker ___ _

[issue40806] itertools.product not lazy

Rémi Lapeyre added the comment: Hi Ramil, itertools.product() expect its argument to be finite iterables, it needs to keep all their elements in memory anyway at it "cycles around" to produce all possible pairs. Basically, product(x(1), x(2)) is equivalent to product(tuple(x(1)), tuple(x(2))

[issue40806] itertools.product not lazy

Change by Rémi Lapeyre : -- nosy: +rhettinger, tim.peters ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe: http

[issue40806] itertools.product not lazy

New submission from Ramil Nugmanov : def x(y): while True: yield y p = product(x(1), x(2)) next(p) # this string will never be reached. -- components: Library (Lib) messages: 370201 nosy: nougmanoff priority: normal severity: normal status: open title: itertools.product n