[tomck]

I think you replied to the wrong person.

That being said, I don't understand your `is_something_true` example.

> It's very often used to do 1 thing at a time when N things could be done instead

That's true, but I don't think e.g. fibres fare any better here. I would say that expressing that type of parallel execution is much more convenient with async/await and Promise.all() or whatever alternative, compared to e.g. raw promises or fibres.

[vjerancrnjak]

I replied directly to you. There are valid arguments as to why async-await sucks, even after you're deeply familiar with how it works. Even though it's just generators/coroutines beneath, async-await pollutes the code completely if you're not strict about its usage.

`is_something_true` is very simple, if condition is true, and then inside the block, if you were to check again it can be false, something that can't happen in synchronous code, yet now, with async-await, it's very easy to get yourself into situations like these, even though the code seems to yell at you that you're in the true branch. the solution is adding a lock, but with such ease to write async-await, it's rarely caught

[tomck]

> I replied directly to you

My comment was responding only to the person who equated threads and async. My comment only said that async and threading are completely orthogonal, even though they are often conflated

> `is_something_true` is very simple, if condition is true, and then inside the block, if you were to check again it can be false, something that can't happen in synchronous code

It can happen in synchronous code, but even if it couldn't - why is async/await the problem here? what is your alternative to async/await to express concurrency?

Here are the ways it can happen:

1. it can happen with fibers, coroutines, threads, callbacks, promises, any other expression of concurrency (parallel or not!). I don't understand why async/await specifically is to blame here.

2. Even without concurrency, you can mutate state to make the value of is_something_true() change.

3. is_something_true might be a blocking call to some OS resource, file, etc - e.g. the classic `if (file_exists(f)) open(f)` bug.

I am neutral on async/await, but your example isn't a very good argument against it

Seemingly nobody ever has any good arguments against it

> async-await pollutes the code completely if you're not strict about its usage

This is a good thing, if a function is async then it does something that won't complete after the function call. I don't understand this argument about 'coloured functions' polluting code. if a function at the bottom of your callstack needs to do something and wait on it, then you need to wait on it for all functions above.

If the alternative is just 'spin up an OS thread' or 'spin up a fiber' so that the function at the bottom of the callstack can block - that's exactly the same as before, you're just lying to yourself about your code. Guess what - you can achieve the same thing by putting 'await' before every function call

Perhaps you have convinced me that async/await is great after all!