[marcus_holmes]

Only newbies tend to complain about `err != nil` in my experience. After a certain point it just clicks and they get used to it. There's a cadence to Go code (do the thing, check the error, do the thing, check the error) that is easy to read once you're used to it, but looks horribly verbose when you're coming from an exceptions-based language.

Go has simplicity as a design goal. Part of that simplicity is not adding all the features we can think of to the language. Just because it would provide slightly leaner syntax for a relatively small group of use cases isn't a good reason to add new language features (imho, from my 10+ years using Go and watching it evolve).

If we can implement this using current language features, but it's complex and messy to implement, then it's a great case for a new library, possibly even inclusion in the standard library. If we can't implement this at all using current language features, then maybe it's a case for a new language feature to enable this. If we can implement it relatively cleanly using current language features, then we're good and don't need to do anything. This seems like a "can implement, but not very cleanly" case, which would be a great justification for a library, but not a language feature. Again, imho.

[jwestbury]

I'm used to `err != nil`, but it doesn't mean I like it. It's a lot of what amounts to boilerplate in a language that is mercifully short of boilerplate elsewhere. This is doubly true when you want custom error types, and need to start unpacking values from your custom error struct.

[hgsgm]

>This seems like a "can implement, but not very cleanly" case, which would be a great justification for a library, but not a language feature.

First sentence of OP:

> This post is about why we need a coroutine package for Go

Then in the girst section after the intro:

> Later, I will argue for an optimized implementation provided directly by the runtime, but that implementation should be indistinguishable from the pure Go definition.

[marcus_holmes]

Yeah, so I'm agreeing that this would be a great library, but disagreeing that it should be a language feature. Sorry if I didn't make that clear.

[alphazard]

Personally, I don't really see anything wrong with explicit error values, and checking them against nil.

The point I was trying to make is that some amount of people see the benefit in removing much smaller boilerplate. And so presumably at least as many people should see the benefit of removing a larger amount of boilerplate.

I'm just talking about the benefits here. There is also a cost to expanding the language. The costs might outweigh the benefits, but it doesn't mean that the benefits don't exist.

[marcus_holmes]

> There is also a cost to expanding the language. The costs might outweigh the benefits, but it doesn't mean that the benefits don't exist.

Agreed. I think this is where the discussion will focus. I'm glad that historically the Go team have weighted the costs heavily, and hope they continue to do so.

I guess I'm in the minority but boilerplate really doesn't bother me. Going the other way gets too much "magic" and we lose the ability to fine-tune behaviour.