Honestly, despite that blog, async coloring is a feature. The pattern enforces implicit critical sections between yields and the coloring is how the dev can know what will yield.
This is a really interesting point. You almost never hear async function coloring being conceptualized as a feature rather than a hindrance. Async function coloring is kind of analogous to the borrow checker in Rust. It makes you think about concurrency the same way that the borrow checker makes you think about memory ownership and lifetimes.
async is a great feature if you use it from square 1. If you start with a legacy codebase using callbacks and try to port it incrementally to async, you're gonna have a bad time. Otherwise, it's definitely a feature
Yeah upgrading a legacy codebase that uses callbacks is not fun, but if the callback functions follow the Node error first value second convention, then it's a little bit easier because you can just use `util.promisify` to convert them to promises in Node. There's also the new Promise.withResolvers method which helps a bit too [1].
For some reason requiring the programmer to use additional syntax at the call site to mark behavioural properties of called functions is not a popular language feature generally. I guess eg TypeScript could add it as a user extensible feature. Would it be useful to be able to require things like this in your internal API?
let gizmos = nocheckperms lookupRequestedGizmos(request);
You're trading complexity for expressiveness but the await keyword syntax is essentially unwrap sugar. Dereferencing a pointer is similar syntax.
It's possible to write a language where awaiting a task is done through a method on the task type. I don't think this is ideal because the whole reason you're using explicit yield points is so you can tell when something yields. Using method syntax makes that harder to see at a glance.