US 39-099 23.3.6.4 [indirectcallable.indirectinvocable] Incorrectly constrained projections

[wg21bot]

Range algorithms which take projections are improperly constrained on the combination of callable/value/reference/projection types, rejecting valid code.

Proposed change:

Adopt P2609.

[JeffGarland]

LWG already saw this paper in Kona and it needs revision before adoption.

cplusplus/papers#1271

[jensmaurer]

LEWG said in cplusplus/papers#1271 "for C++26"; doesn't that mean the NB comment (which applies to C++23) is rejected?

[timsong-cpp]

@JeffGarland There's a new revision at https://isocpp.org/files/papers/P2609R2.html

@jensmaurer I don't believe LEWG ever discussed the NB comment.

[JeffGarland]

Thanks @timsong-cpp I missed the revision - adding to the Issaquah schedule.

[JeffGarland]

Reviewed and approved at Issaquah -- see paper issue for details.