1119. tuple query APIs do not support references

Section: 22.4.7 [tuple.helper] Status: NAD Submitter: Alisdair Meredith Opened: 2009-05-23 Last modified: 2016-01-28 10:19:27 UTC

Priority: Not Prioritized

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The tuple query APIs tuple_size and tuple_element do not support references-to-tuples. This can be annoying when a template deduced a parameter type to be a reference, which must be explicitly stripped with remove_reference before calling these APIs.

I am not proposing a resolution at this point, as there is a combinatorial explosion with lvalue/rvalue references and cv-qualification (see previous issue) that suggests some higher refactoring is in order. This might be something to kick back over to Core/Evolution.

Note that we have the same problem in numeric_limits.

[ 2009-10 post-Santa Cruz: ]

Move to Open. Alisdair to provide wording.

[ 2010 Rapperswil: ]

Move to NAD. This is an extension after the FCD, without a clear motivation. May consider as NAD Future if motivating examples come forward.

Proposed resolution: