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  1. Qt
  2. QTBUG-104152

Impact of C++20 CTAD on our code

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    • Epic
    • Resolution: Unresolved
    • P4: Low
    • None
    • None
    • Core: Other
    • None
    • C++20 CTAD @ Qt

    Description

      C++20 added support for CTAD (https://en.cppreference.com/w/cpp/language/class_template_argument_deduction) for

      1. aggregates (__cpp_deduction_guides >= 201907L)
      2. aliases (__cpp_deduction_guides >= 201907L)

      The first is not really interesting, because we can emulate it using user-defined deduction guides, and we'd get the same result in C++17 and C++20. Once we can depend on C++20, I expect more classes to become simple structs as a result of this change, designated initializers (QTBUG-104153) and __cpp_aggregate_paren_init (QTBUG-104154).

      The second is interesting for our users, but doesn't affect our APIs.

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          Epic - Created by Jira Software - do not edit or delete. Issue type for a big user story that needs to be broken down. QTBUG-99243 Initiative: Qt and C++20

          • P2: Important - Urgent, should be fixed, but will not stop the release.
          • Open

          User Story - Created by Jira Software - do not edit or delete. Issue type for a user story. QTBUG-109362 C++20 is mandatory for users of Qt (Phase III)

          • Not Evaluated - Not yet evaluated/prioritized
          • Open
          relates to

          Epic - Created by Jira Software - do not edit or delete. Issue type for a big user story that needs to be broken down. QTBUG-104153 Impact of C++20 designated initializers on our code

          • P3: Somewhat important - Should be fixed, but doesn't affect the release in any way.
          • Open

          Epic - Created by Jira Software - do not edit or delete. Issue type for a big user story that needs to be broken down. QTBUG-104154 Impact of C++20 aggregate init with parentheses on our code

          • P3: Somewhat important - Should be fixed, but doesn't affect the release in any way.
          • Open
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              cnn Qt Core & Network
              mmutz Marc Mutz
              Vladimir Minenko Vladimir Minenko
              Alex Blasche Alex Blasche
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                Updated:

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