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Comment by rlander | Hacker News Reader

> Async everything

What do you mean by that? Most code in Erlang/Elixir is synchronous, meaning it will block the process (but not the scheduler). Maybe you meant concurrent (or message-passing) everything?

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Yeah I'm curious too.

I've written about 2,000 lines of code on this course platform so far and everything except for 1 function is synchronous from a "this is my code" standpoint. I only used Task.start once to launch something in the background.

All of the GenServer stuff is built on top of regular Erlang processes. It's all async. You'll might find out when your server gets busy and GenServer calls start timing out

In the Erlang VM, process execution can stop at an arbitrary point and resume later on. This time slicing is done to ensure that no process, takes up too much time. So you must treat your code as asynchronous since if you get a value from another module, then get it again in the next line it might have changed because your process was suspended in between those two lines.

While that is true it does not make a difference for day to day programming, unless you are super accustomed to think about locks.

You can get very far in Elixir without considering the nitty gritty parts of OTP.

It's interesting that people would like Elixir without understanding OTP.

Some of us like to have productive junior devs that can ease into an understanding of otp.

This is what I like about it: my junior had an ask from management to profile a customer task, as a single process, and as a concurrent job to simulate more than one simultaneous client. I'm nonzero suspicious it was asked to try to get him to trip up and have an excuse to can him. I instructed him to do the job in elixir. He got it done, then I wrapped it in task.async one-line, and it just worked and he understood what was going on, and was able to generalize the concurrency rules.

The elixir standard library is just full of things that make your concurrent programming seamless, easy, and bulletproof, even for a junior that's never done things that way.

I can't imagine him getting this correct with python async, JavaScript promises and callbacks, or having to create go channels.

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