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3245. Unnecessary restriction on'%p' parse specifier

Section: 30.13[time.parse]Status:C++20Submitter: Tomasz KamińskiOpened: 2019-07-31Last modified: 2021-02-25

Priority:0

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Discussion:

The current specification for the'%p' flag in "[tab:time.parse.spec]Meaning ofparse flags" places a restriction of it'splacement with regards to the'%I' command:

The locale's equivalent of the AM/PM designations associated with a 12-hour clock.The command%I must precede%p in the format string.

This restriction makes the migration to new API more difficult, as it isnot present for thePOSIXstrptimenor in theexample implementation of the library. Per Howard's comment:

Actually this is an obsolete requirement and it should be struck. Thefirst time I implemented this I didn't know how to do it without thisrequirement. I've since reimplemented it without needing this.

[2019-08-17 Issue Prioritization]

Status to Tentatively Ready and priority to 0 after eight positive votes on the reflector.

Proposed resolution:

This wording is relative toN4830.

1. Modify Table 99 "Meaning ofparse flags [tab:time.parse.spec]" in30.13[time.parse] as indicated:

   Table 99: Meaning ofparse flags [tab:time.parse.spec]

   Flag	Parsed value
   […]
   %p	The locale's equivalent of the AM/PM designations associated with a 12-hour clock.The command%I must precede%p in the format string.
   […]