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### 3621. Remove feature-test macro `__cpp_lib_monadic_optional`

Section: 17.3.2 [version.syn] Status: WP Submitter: Jens Maurer Opened: 2021-10-18 Last modified: 2022-02-10

Priority: Not Prioritized

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Discussion:

P0798R8 "Monadic operations for `std::optional`" created a new feature-test macro `__cpp_lib_monadic_optional` for a relatively minor enhancement.

We should instead increment the value of the existing feature-test macro `__cpp_lib_optional`.

[2022-01-29; Reflector poll]

Set status to Tentatively Ready after eight votes in favour during reflector poll.

[2022-02-10 Approved at February 2022 virtual plenary. Status changed: Tentatively Ready → WP.]

Proposed resolution:

This wording is relative to N4901.

1. Modify 17.3.2 [version.syn] as indicated:

   >     […]
   >     #define __cpp_lib_monadic_optional 202110L // also in <optional>
   >     […]
   >     #define __cpp_lib_optional 202106L202110L // also in <optional>
   >     […]