oliEver wanted to prevent someome from calling your expensive function at runtime? With the power of (very) unstable features you can (starting tomorrow, https://github.com/rust-lang/rust/pull/157647 just landed):
```rust
#[rustc_comptime]
fn boom() {}
fn main() {
boom() // error
}
```
The reflection/type_info stuff uses it now, as we only have builtin compile time reflection (which you can use to build your own runtime reflection)
Start using comptime for reflection intrinsics and their wrapper functions by oli-obk · Pull Request #157647 · rust-lang/rust
r? @fee1-dead follow-up to #148820 I needed to add some more rustc code because turns out I forgot to add tests to the previous PR which actually codegen while using comptime fns. Check builds neve...
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Harry Wood