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Comment by everybodyknows | Hacker News Reader

Nomination for RSC's greatest technical contribution: module versioning. Absolutely fundamental to the language ecosystem.

https://research.swtch.com/vgo-intro

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Agreed, see the index of those posts: https://research.swtch.com/vgo

Other contenders I find myself sharing and re-reading:

- https://swtch.com/~rsc/regexp/regexp1.html

- https://swtch.com/~rsc/regexp/regexp4.html

- https://research.swtch.com/bisect

- https://research.swtch.com/zip

The interesting thing is - this went pretty much against the community at the time.

At the time, the community seemed to have settled on dep - a different, more npm-like way of locking dependencies.

rsc said "nope this doesn't work" and made his own, better version. And there was some wailing and gnashing of teeth, but also a lot of rejoicing.

That makes me a bit sad that rsc is leaving.

On the other hand, I don't really like the recent iterator changes, so maybe it's all good.

Btw if you reading this rsc, thanks a lot for everything, go really changed my life (for the better).

Iterators definitely have one of the strangest syntaxes I've seen, but if you promise not to break the language you better not introduce new syntax without a Major reason (like generics, but even those actually introduced next to no new syntax, even re-using interfaces o_O).

Iterators don’t really introduce any new syntax, strange or otherwise.

That's what he said

In part of the comment yes, kind of, but the comment begins by saying "Iterators definitely have one of the strangest syntaxes I've seen". As there is no syntax specific to iterators in Go, I find this a bit hard to understand.

Well, yes, that's the thing: you don't get any special syntax for generators (like "yield" keyword), which makes them look quite weird compared to other languages that have native support for them. You need to have very clunky and verbose syntax (at least I view it as such) which consists of having to define an extra nested closure and use a function pointer that was passed to you. Having a new keyword would allow for a much nicer looking generator functions, but that would break all existing tooling that doesn't yet support that keyword (and potentially break existing programs that use yield as a variable name or something like that).

Seems like a total non-issue to me. It’s conceptually very easy to grasp and follows the normal Go syntax for defining functions. And what percentage of your code base is really going to consist of custom iterators? A syntactic shortcut might save you two lines of code for every 5000 you write. A lot of Go programmers will probably never write a custom iterator from scratch. The important thing is to make the custom iterators easy to use, which I think has been achieved. I’m sure they’ll consider adding some syntax sugar in time, but it would be a trivial convenience.

The benefit of Go’s generator implementation is a huge simplificación of the language semantics compared to other approaches. The generator function has no special semantics at all, and when used with ‘range’, all that occurs is a very simple conversion to an explicit loop repeatedly calling the function. Other popular approaches require either special runtime support for coroutines of some form, or a much more elaborate translation step within the compiler.

s/syntax/API/

It's not that hard to understand what OP means.

It's just the visitor pattern, taught in software engineering 101. A function that takes a callback function that gets called for each visited value. Nothing strange about it. Many standard library functions such as sync.Map.Range or filepath.Walk have always used it. The new thing is that it now gets easier to use on the caller side.

The sync.Map.Range, filepath.Walk and other similar functions with visitor pattern in standard Go packages will remain there forever because of backwards compatibility. This means that new functions must be added to standard Go packages in order to be able to use them with iterators starting from Go 1.23. This complicates Go without reasonable benefit:

- You need to be able maintaining code with multiple ways to iterate over various collections in standard Go packages.

- You need to spend time on deciding which approach for iteration to use when you write new code.

Plenty of people in the community considered dep way too messy to be the real solution.

One I enjoyed a lot (a lot) was this one https://research.swtch.com/pcdata

Hope he gives us more in the future

thanks rsc

Fundamentally broken model of versioning, but I guess nobody really cares.

Can you elaborate on what problems you have with the MVS algorithm?

Not really a fan at all. Dep and its predecessors followed kiss principles, were easy to reason about, and had great support for vendoring.

I’ve wasted so much time dealing with “module hell” in go, that I never dealt with in the prior years of go usage. I think it has some major flaws for external (outside Google) usage.

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