与Python等其他语言相比，golang中的WaitGroup是否向后退一步？

Question

I am very new to golang and I was trying out goroutine, while it's quite easy to run things concurrently, I am a bit surprised the way golang to "join the threads" using WaitGroup.

As far as I know, the goroutine needs to have reference to the WaitGroup object to call Done(), which means, I have to either make the goroutine to accept a WaitGroup object, or make WaitGroup object global to the goroutine.

But in other languages like Python, you call thread.join(), the "controlling" part sits outside of the thread code.

Like I said, I am very new to golang, I don't know why it was designed this way, could someone please shed some light on this aspect?

UPDATE: I hope the argument is not based on 'Goroutine vs Thread', at the end of the day they both try to achieve (some kind of) 'concurrency', my question is more about controlling the program flow.

Answer 1

No, it's just a different thing that does a different thing. They're not even really comparable, since a WaitGroup by its nature waits on multiple things (and can have things added to it during its lifetime) and a python thread's join always just waits on that one thing.

That said, Go's library is more about giving you the primitive things that you need to do more advanced things, while Python's has more of a "batteries included" philosophy. Using what Go gives you, you could create a type that acts quite a bit like a python Thread. It's probably not the best way to make use of Go, but you're given the tools to do it if you want. However the standard library isn't going to standardize on such a thing.