This is a WORK IN PROGRESS page to understand the implications of "Reflection for C++" for the future of Qt and moc.
TL;DR
Reflection in C++26 might be insufficient for replacing moc.
We may require token injection, function definition, string-based lookup; at least the first is C++29 material, don't know about the others.
Extra fancy features like outputting extra JSON files (or embedding JSON in plugins) may be out of scope for this work.
Why?
moc extracts interesting metadata from QObject subclasses / gadgets / namespaces. This metadata is then used at runtime to implement many different QMetaObject facilities.
C++26 will (likely) ship with compile-time reflection. This means that the work that moc does today (as an external tool, with its custom lexer and parser etc.) could be done by the compiler itself. In the future, this may unlock lots of interesting possibilities (e.g. templated QObjects) and reduce technical debt (no need to maintain our own C++ parser for moc).
However, we're not sure how to get there just yet. Some questions that this work aims to answer:
Can we replace moc with a pure C++ solution? Is there something missing from standard C++ that we need for moc?
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