[zozbot234]

> No way anything std::meta gets into serious production

Rust proc macros get used in serious production, even though they're quite slow to compile. Sure, std::meta is probably a bit clunkier, but that's expected from new C++ features as you say.

[Thom2000]

Sadly, Rust proc macros operate on tokens and any serious macro implementation needs third-party crates.

Compile-time reflection, with good, built in API, akin to C# Roslyn would be a real boon.

[galangalalgol]

Any serious anything needs third party crates. Coming from c++ this has been the most uncomfortable aspect of rust to me, but I am acclimating.