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Node compatibility isn’t a language feature, though, and it doesn’t result in “colored” functions. If a Deno library uses a Node API or an npm library somewhere, it can be entirely encapsulated, so you might not even notice until you see it in a stack trace. That doesn’t seem very intrusive?

So it reminds me more of trying to avoid CGO in Go or avoid “unsafe” in Rust.

It would be worse if Node-specific types started appearing as function parameters or return types, but that seems fairly rare even in npm libraries, so it seems easy to avoid.

> If a Deno library uses a Node API or an npm library somewhere, it can be entirely encapsulated, so you might not even notice until you see it in a stack trace. That doesn’t seem very intrusive?

Node API yes, NPM library no. If you add a dependency on a library that uses NPM you now depend on an entire web of transitive NPM dependencies, with all of the problems that entails. People don't dislike NPM because it's aesthetically displeasing—you can't just abstract away the problems with NPM. The ecosystem causes real problems with real software, and Deno initially recognized those real problems and set out to reset the ecosystem.

The only way in which NPM-compat is different than colored functions is that there's no static compiler feature telling you when you've added a dependency on a bunch of NPM libraries.

I think that’s best addressed by avoiding dependencies and looking for libraries with few indirect dependencies. There are lots of npms that advertise few or no dependencies as a feature.

Though, it is nicer if it’s on jsr.io because you’ll see Typescript source code in the debugger.

There’s nothing about starting over that prevents ending up with a whole new rat’s nest of dependencies, if you’re not careful.

I'm not saying it's a realistic view, but I had hoped without any inclusions from NPM there would exist a couple more clean-room (or at least decoupled) implementations of things in TS, leaving everything JS behind.

There is no such thing as a "colorless" alternative to colored functions[1] in Javascript, at least as far as browser-compatibility is concerned. Promises are a convention for what used to be all the colors in the rainbow (and then some imaginary ones). Async/await is syntactic sugar on top that makes it more readable. The inherent pitfalls of asynchronous code don't disappear if you remove that sugar.

If you're gonna argue that fragmentation is a problem in the node ecosystem (which I agree with), you can't convince me that a plethora of approaches to asynchronous code is preferable to async/await and promises.

1) The original essay that coined this term was looking at it from a language design perspective. The argument is a fair one if that design question is up for debate, but that isn't the case for Javascript.

To be clear, I like async. I just don't think "you don't have to use it if you don't like it" is a good argument in favor of it because it's obviously not true.

...but you don't have to use it. You can keep using raw promises and you can trivially use any async/promise-based API with informal callbacks. I doubt many people want to do that, but they can.

Of course, in (browser-compatible) Javascript, some things can not be done synchronously, but that's not up for debate.

Not the person you're replying to, but I don't get how your argument applies here. JS functions could already return promises. Some of them being declared as async doesn't change anything for the consumer does it?

(In general, I do agree that "you don't have to use it" is not a strong argument.)

Using the function color concept was an example of a place where this problem can occur, not the actual problem.

The problem is that if you think statically, you can say "oh, just use the 'clean' subset". But the world is not static. If you think dynamically, you can see the full Node ecosystem as a fairly powerful attractor; why would I write a deno library that only works on deno when I can write a node library that works on both? Well, if I'm writing in the Node ecosystem, why not use the whole thing?

This is a general effect; it is very hard for people to set up long-term ecosystems that are "too close" to existing ecosystems. Generally the new thing will either get pulled in (as in this case) or ignored (as in the many cases of 'hey Typescript seems to have worked pretty well, let me do a Typescript-like gloss of this other language', which generally just get ignored). There are successes, like Typescript (JS is in general a special case because being the only language in the browser for so long it was both a language and a compile target; most other attempts to "Typescriptify" a language flounder on the fact that few if any other languages have that situation), Elixir (managed to avoid just being absorbed by Erlang, IMHO kind of a similar situation where the 'base langauge' for the ecosystem was not really the best), and the occasional Lisp variant that bubbles up (though like Clojure, usually with a story about where it can be run), but in general this is very hard to pull off, harder in some ways than simply starting a brand new language ecosystem, which is itself no picnic.

I'm not talking about JS. I had Rust in mind.

Also, promises already color functions just like callbacks do. Async/await just changes the syntax by which that coloring is expressed. The real problem people have with async is that they prefer green threads as a solution to concurrency, not that they don't like the syntax.

Why are people so resistant to change lol just use the better stuff or migrate to it.

It’s software you are mostly using to build end user software. Gauge it by how well it works and serves the end user.

This is why AI is good. It will just force this SWE vintage to solve the problem at hand instead of over engineering or holding on to some traditionalist views of the language.

Off-topic, but the idea of "colored functions" from the "What Color is Your Function" article doesn't apply to Rust's async/await. That article is about JavaScript before it had async/await, when it used callbacks.

In Rust, you can call async functions from normal ones by spawning them on the executor. The .await syntax isn't as painful as dealing with callbacks and closures in JavaScript. Plus, if you call an async function incorrectly, Rust's compiler will catch it and give you a clear error message, unlike JavaScript, where bad function calls could lead to unpredictable behavior. The premises of the article don't apply, so Rust's async/await doesn't introduce the same "colored function" issues.

I read the article when it hit HN months ago but I don't agree that function coloring doesn't apply. What you're describing is that Rust makes coloring less painful, not that functions aren't colored.

JavaScript itself has come a long way towards making coloring less painful. TypeScript+ESLint solves the weird unpredictable behavior issues with JS and async/await solves the syntax issue. Promises in general give well-defined semantics to calling an async function from a sync function. But all that only undoes some of the arguments about function coloring, not all of them. Fundamentally the same question applies: do you make async-ness part of the type system or do you instead build a system like green threads that doesn't put it in the type system?

I happen to think that coloring functions according to their async-ness is actually the right move (with the right ergonomic improvements), but plenty of people don't agree with me there even with all the ergonomic improvements Rust and TypeScript have made to the model.