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Reading the “Kotlin Coroutines” book, it just dawned on me that `CoroutineContext` is basically the coroutines’ equivalent of `ThreadLocal`. Why don’t the tutorials say this? Would make understanding so much faster…

<https://elizarov.medium.com/phantom-of-the-coroutine-afc63b03a131>

I think the two paradigms (threads vs coroutines) are different enough that drawing that comparison might just create more confusion

I agree, it’s not equivalent. Maybe “similar” is better.

I was just completely confused as to what a coroutine context *was* until the parallel to threadlocal dawned on me.

Not sure I agree with that article. Can’t you think of the chain of `Continuation`s are the coroutine?

You'd have to take that up with Roman :smile:. He probably knows what he's talking about, though, he was the project lead on coroutines and now on all of Kotlin

If I had to take a stab at an answer, I'd say that the chain of continuations is to the coroutine as the call stack is to the thread

Yes. But what is a thread if not its call stack + a record somewhere in the thread scheduler?

Actually <https://stackoverflow.com/questions/46227462/how-to-use-code-that-relies-on-threadlocal-with-kotlin-coroutines|here is a StackOverflow post>, also from Roman, where he says that "Coroutine's analog to `ThreadLocal` is `CoroutineContext`". So maybe this is something that could be mentioned in the documentation. I agree with you that it would give a good starting point for understanding, even if the comparison is inexact.