public inbox for gcc-bugs@sourceware.org help / color / mirror / Atom feed
From: "gcc-bugs at marehr dot dialup.fu-berlin.de" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug libstdc++/95322] New: std::list | take | transform, expression does not work cbegin() == end() Date: Mon, 25 May 2020 18:16:15 +0000 [thread overview] Message-ID: <bug-95322-4@http.gcc.gnu.org/bugzilla/> (raw) https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95322 Bug ID: 95322 Summary: std::list | take | transform, expression does not work cbegin() == end() Product: gcc Version: 10.1.1 Status: UNCONFIRMED Severity: normal Priority: P3 Component: libstdc++ Assignee: unassigned at gcc dot gnu.org Reporter: gcc-bugs at marehr dot dialup.fu-berlin.de Target Milestone: --- Hello gcc-team, I'm not sure if this is intended behaviour, or if this is a defect in the standard, or something that you should never write in a generic context. ASFAIK you can use that expression on any container and on any view, but not on some(?!) combinations of views? This is a bit unexpected. ```c++ #include <concepts> #include <list> #include <ranges> int main() { std::list v{0,1 ,2, 3, 4, 5, 5, 6}; // works if std::vector auto view1 = v | std::views::take(5); auto view2 = v | std::views::transform([] (int i) { return i + 3;}); auto view3 = view1 | std::views::transform([] (int i) { return i + 3;}); std::ranges::cbegin(view1) == std::ranges::end(view1); // works std::ranges::cbegin(view2) == std::ranges::end(view2); // works std::ranges::cbegin(view3) == std::ranges::end(view3); // does not work return 0; } ``` https://godbolt.org/z/4Nzr69
next reply other threads:[~2020-05-25 18:16 UTC|newest] Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top 2020-05-25 18:16 gcc-bugs at marehr dot dialup.fu-berlin.de [this message] 2020-05-26 13:13 ` [Bug libstdc++/95322] " redi at gcc dot gnu.org 2020-05-26 13:18 ` redi at gcc dot gnu.org 2020-05-26 13:21 ` redi at gcc dot gnu.org 2020-05-26 13:54 ` ppalka at gcc dot gnu.org 2020-05-26 20:45 ` cvs-commit at gcc dot gnu.org 2020-05-27 20:00 ` redi at gcc dot gnu.org 2020-05-27 20:04 ` daniel.kruegler at googlemail dot com 2020-05-27 20:29 ` redi at gcc dot gnu.org 2020-05-27 21:08 ` cvs-commit at gcc dot gnu.org 2020-05-27 21:11 ` redi at gcc dot gnu.org 2020-05-28 1:48 ` cvs-commit at gcc dot gnu.org 2020-05-28 18:51 ` daniel.kruegler at googlemail dot com 2020-07-09 12:59 ` cvs-commit at gcc dot gnu.org 2020-07-09 14:51 ` redi at gcc dot gnu.org 2020-07-09 17:54 ` gcc-bugs at marehr dot dialup.fu-berlin.de 2020-08-27 1:53 ` cvs-commit at gcc dot gnu.org 2020-10-12 17:48 ` cvs-commit at gcc dot gnu.org 2020-10-21 1:57 ` cvs-commit at gcc dot gnu.org 2020-12-01 16:20 ` cvs-commit at gcc dot gnu.org
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=bug-95322-4@http.gcc.gnu.org/bugzilla/ \ --to=gcc-bugzilla@gcc.gnu.org \ --cc=gcc-bugs@gcc.gnu.org \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions for how to clone and mirror all data and code used for this inbox; as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).