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Comment by d0mine | Hacker News Reader

> dreadful language to try to do concurrency in due to its global interpreter lock

don't take it too seriously. GIL has its issues and it would be nice to see it gone but "dreadful" is an overstatement. Python wouldn't be so widely used as a back-end language otherwise. Concurrency is not parallelism.

On "it [Go] will become a model for how concurrency is managed in future languages." -- it is not as clear cut as it appears at the first glance: "Notes on structured concurrency, or: Go statement considered harmful" https://vorpus.org/blog/notes-on-structured-concurrency-or-g...

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Dreadful may be a little strong but anytime I've tried to implement something like asyncio for a non trivial piece of code it becomes pretty obtuse. (imo)

I’ve found asyncio to be a very simple model to understand, using the aio libs: aiohttp, aiopg, aiobotocore, etc.

Basically just slap “async” or “await” in front of everything and understand that anytime there is a network connection being accessed, that method will release control of the main thread.

You just have to pay attention to where something might block the thread for any significant amount of time - heavy calculation or lengthy file IO

You can spawn a multitiude of async tasks on startup and have super basic “scheduling” by using asyncio.sleep with some jitter.

The only time I have seen the performance limits of a naive asyncio app reached was in an auth app that sat in front of every API request for the whole company, and even then it was an obscure DB connection pool management issue deep in psycopg2.

goroutines (and the go keyword) are the primitive, just like async is the primitive for python. Something like golang.org/x/sync/errgroup gives Go the same kind of "nursery" concept and can be leveraged almost identically (modulo Go not having the "with" concept, but defer can play the same role)

there is no doubt that a "nursery"-like construction can be implemented in Go in the same way like any language with "goto" can implement structured loops. The point is in constraining what can be done.

There is a trade off: "goto" is powerful but it is likely to lead to a spaghetti code. "nursery" introduces constrains but makes it easier to deal with error handling/cleanup, back pressure issues such as https://lucumr.pocoo.org/2020/1/1/async-pressure/

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