> I can’t think of any other language in my 45 years long career that surprised more than Zig. I can say the same (although my career spans only 30 years), or, more accurately, that it's one of the few languages that surprised me most. Coming to it from a language design perspective, what surprised me is just how far partial evaluation can be taken. While strictly weaker than AST macros in expressive power (macros ar…
Great comment! I agree about comptime, as a Rust programmer I consider it one of the areas where Zig is clearly better than Rust with its two macro systems and the declarative generics language. It's probably the biggest "killer feature" of the language.
IMHO "clearly better" might be a matter of perspective; my impression is that this is one of those things where the different approaches buy you different tradeoffs. For example, by my understanding Rust's generics allows generic functions to be completely typechecked in isolation at the definition site, whereas Zig's comptime is more like C++ templates in that type checking can only be completed upon instantiation. I believe the capabilities of Rust's macros aren't quite the same as those for Zig's comptime - Rust's macros operate on syntax, so they can pull off transformations (e.g., #[derive], completely different syntax, etc.) that Zig's comptime can't (though that's not to say that Zig doesn't have its own solutions).
Of course, different people can and will disagree on which tradeoff is more worth it. There's certainly appeal on both sides here.