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Section: 23.6.9.1 [flat.multimap.overview] Status: New Submitter: Jonathan Wakely Opened: 2025-09-05 Last modified: 2025-09-05
Priority: Not Prioritized
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Discussion:
23.6.9.1 [flat.multimap.overview] p4 says:
Except as otherwise noted, operations onflat_multimap
are equivalent to those offlat_map
, except thatflat_multimap
operations do not remove or replace elements with equal keys.[Example 1:
flat_multimap
constructors and emplace do not erase non-unique elements after sorting them. — end example]
This doesn't really work, because there is no flat_map
operation that is
equivalent to the constructors and insert
and insert_range
functions that
take a sorted_equivalent_t
tag argument. The flat_map
operations that the
wording intends to refer to take a sorted_unique_t
tag argument.
It's a bit of a stretch to say they're equivalent when they don't even have
the same parameters, so we need some weasel words here.
Proposed resolution: