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2830. insert_return_type is only defined for containers with unique keys

Section: 21.2.6 [associative.reqmts], 21.2.7 [unord.req] Status: Resolved Submitter: Daniel James Opened: 2016-11-24 Last modified: 2017-02-02

Priority: Not Prioritized

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The requirements for associative and unordered associative containers list insert_return_type for all containers, but looking at the class description in [map.overview], [multimap.overview] etc. it's only defined for containers with unique keys. Jonathan Wakely pointed out that this depends on the resolution of LWG 2772, which might remove insert_return_type completely.

A possible resolution would be to put in 21.2.6 [associative.reqmts]: 'insert_return_type (map and set only)' and in 21.2.7 [unord.req]: 'insert_return_type (unordered_map and unordered_set only)'. Or maybe something like '(containers with unique keys only)'.

[Issues Telecon 16-Dec-2016]

Resolved by adoption of P0508R0.

Proposed resolution: