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Reflection for C++26

(isocpp.org)
196 points svlasov | 1 comments | 30 Jun 24 11:26 UTC | HN request time: 0.221s | source
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Dwedit ◴[01 Jul 24 22:04 UTC] No.40851285[source]▶
Compile time or runtime? Compile time reflection would be completely painless and bloat-free.
replies(3): >>40851300 #>>40851330 #>>40851736 #
shortrounddev2 ◴[01 Jul 24 22:08 UTC] No.40851330[source]▶
RTTI is a super vital feature for deserializing without having to generate code or write a ton of tedious boilerplate. I'd be very happy with RTTI in C++ and my life would be instantly easier if there were RTTI in typescript so I didn't have to use any of the hacky solutions out there for deserializing JSON on backends without RTTI.

I suppose C++'s template system might be able to generate JSON deserializers with static reflection as well

replies(2): >>40851369 #>>40851644 #
chongli ◴[01 Jul 24 22:13 UTC] No.40851369[source]▶
You don't need RTTI to deserialize data in a clean way. What you need is return-type polymorphism. Haskell has this and it makes writing serializers and deserializers symmetric and totally painless.
replies(1): >>40851442 #
fooker ◴[01 Jul 24 22:20 UTC] No.40851442[source]▶
Return type polymorphism and inheritance doesn't mix very well.

Swift got into this mess early in it's lifecycle and it's type checking is still more expensive than the rest of the compiler combined, and unpredictable on top of that.

replies(2): >>40851982 #>>40852119 #
1. chongli ◴[01 Jul 24 23:35 UTC] No.40851982[source]▶
Yeah if you ask me, inheritance is the one to go. Every time. Inheritance just makes things more complicated. It’s not a great tool of abstraction.