I find the Zig example to be shocking.
It's just so brittle. How can anyone think this is a good idea?
replies(5):
It's just so brittle. How can anyone think this is a good idea?
It is a tradeoff between making some things easier. And probably compiler is not mature enough to catch this mistake yet but it will be at some point.
Zig being an auteur language is a very good thing from my perspective, for example you get this new IO approach which is amazing and probably wouldn’t happen if Andrew Kelley wasn’t in the position he is in.
I have been using Rust to write storage engines past couple years and it’s async and io systems have many performance mistakes. Whole ecosystem feels like it is basically designed for writing web servers.
An example is a file format library using Io traits everywhere and using buffered versions for w/e reason. Then you get a couple extra memcopy calls that are copying huge buffers. Combined with global allocation everywhere approach, it generates a lot of page faults which tanks performance.
Another example was, file format and just compute libraries using asyncio traits everywhere which forces everything to be send+sync+’static which makes it basically impossible to use in single thread context with local allocators.
Another example is a library using vec everywhere even if they know what size they’ll need and generating memcopies as vec is getting bigger. Language just makes it too easy.
I’m not saying Rust is bad, it is a super productive ecosystem. But it is good that Zig is able to go deeper and enable more things. Which is possible because one guy can just say “I’ll break the entire IO API so I can make it better”.
Obviously nobody knows they've made this mistake, that's why it is important for the compiler to reject the mistake and let you know.
I don't want to use an auteur language, the fact is Andrew is wrong about some things - everybody is, but because it's Andrew's language too bad that's the end of the discussion in Zig.
I like Rust's `break 'label value`. It's very rarely the right thing, but sometimes, just sometimes, it's exactly what you needed and going without is very annoying. However IIUC for some time several key Rust language people hated this language feature, so it was blocked from landing in stable Rust. If Rust was an auteur language, one person's opinion could doom that feature forever.