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basic_const_iterator
doesn't work with optional
Section: 25.5.3 [const.iterators] Status: New Submitter: Hewill Kang Opened: 2023-08-26 Last modified: 2023-10-30
Priority: 3
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Discussion:
The heterogeneous comparison operators of basic_const_iterator
only constrain type I
to be
comparable with the underlying iterator type, which allows non-iterator types such as optional
, and
the heterogeneous comparison operators of the latter would make the situation worse
(demo):
#include <iterator> #include <optional> int main() { std::basic_const_iterator<const int*> it; std::optional opt{it}; auto c = opt < it; // infinite meta-recursion auto d = it - opt; // infinite meta-recursion }
[2023-10-30; Reflector poll]
Set priority to 3 after reflector poll.
Proposed resolution: