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Comment by necubi | Hacker News Reader

I think that's totally backwards. A good type system _improves_ iteration speed, it doesn't slow you down. When I refactor a Rust program, I have very high confidence that if it compiles, I haven't accidentally introduced a bug.

I don't write much Go code, but my company does. I have seen so many incidents and bugs whose root cause was: someone changed a library, that broke the semantics that users were relying on, but everything still compiled fine, so nobody noticed the subtly wrong behavior for a long time. An incredible amount of money has been lost like this.

Go simply does not give you the tools to prevent these issues in the type system, you have to rely on really thorough unit tests (which inevitably don't get written in the spirit of "moving fast".)

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Wait what?! Most of the major go libs (std and not) have been stable for years. Rust is merging random syntaxes and random packages get upgraded to std lib all the time.

The package ecosystem was so stable that go didn’t ship with a package manager (not saying it’s good but definitely a sign of relative stability).

Besides nil pointers (typesystem could do better here) and bad logic (can’t do better but language simplicity reduces this), what you’re saying is definitely not the experience of the majority. People constantly talk about being able to go to a golang program from 8 years ago and run it with no problems. Rust changes every few weeks.

Not to mention go compiles at the speed of light, so CI pipes are usually just rebuild and rerun the entire suite on every commit, so idk how such bugs would lurk unless the tests were lackluster. Which happens, I totally understand.

I don’t know what Rust you’ve been using, but they’ve been explicitly having all changes be backwards compatible since 2016 - when they hit 1.0 - with a few small changes in 2018.

> People constantly talk about being able to go to a golang program from 8 years ago and run it with no problems. Rust changes every few weeks.

You stated that "Rust is merging random syntaxes and random packages get upgraded to std lib all the time" as though it were incompatible with "being able to go to a program from 8 years ago and run it with no problems". But there's no incompatibility here. Rust adds new features at a faster rate than Go does, but it also maintains backwards compatibility ("stability without stagnation").

Sure, I conflated 'still compiles' with 'still the right pattern'. Its sorta like Javascript, ECMAscript has been backwards compatible but the ecosystem is a consistently moving target that users have to adopt their code to or feel left behind. E.g crossbeam and parkinglot. Also the bunch of nightly features that disappear but many use.

Sure the mainline stays clean but thats not what matters in practice.

> The package ecosystem was so stable that go didn’t ship with a package manager (not saying it’s good but definitely a sign of relative stability).

Which also explains why you can git clone a Go library/tool and have it not building because some dependencies introduced some breaking changes in the master branch. That happened the last 3 times I wanted to fix something in a Go project.

> Rust is merging random syntaxes and random packages get upgraded to std lib all the time.

I really don't know where this is coming from. The only package that was included into std like this is replacing the hashmap with hashbrown, and this didn't even change the public api of the standard library at all, besides improving performance of the hashmap.

> don't write much Go code, but my company does. I have seen so many incidents and bugs whose root cause was: someone changed a library, that broke the semantics that users were relying on, but everything still compiled fine, so nobody noticed the subtly wrong behavior for a long time. An incredible amount of money has been lost like this.

In all likelihood, that "incredible amount" is a small fraction of the money your company saved in iteration velocity by not using Rust in the first place. This might not be true depending on your domain--if you're writing space shuttle software, bugs can be really expensive. If you're writing ordinary web app backend code, you're probably much better off with Go than Rust.

I'm not sure I understand how this can happen in Go, it's a strongly type language, if for example you change a method / function signature, the code won't compile.

Go is strongly typed (you can't pass an int to a function expecting a string), but its type system is not very powerful, and it cannot express many of the types people need in practice. Back to the discussion at hand (generics), Go programmers usually work around this lack by using interface{} types, which can point to anything and are essentially dynamic typing.

As another example, Go makes it impossible to create a Maybe/Option type which leads to a bunch of issues around returning failing or empty values from functions. In one particularly costly example, there was a function in a library that was getting some price information from a file. Originally this returned nil when the price information could not be loaded, but a refactoring caused it instead to return 0 which the client happily used. This was not caught for _weeks_.

What you're describing comes down to "Bad programmers do bad things", which literally no language can or will solve. If your code has lots of interface{} in it, you're not really using the language as intended. Pretty much every Go styleguide/linter/whatever will throw up at interface{} usage.

You can write unsafe code in Rust. Does that mean that Rust is bad too?

100% agree. Same with :any in typescript. When it comes to bugs... I tend to think that a good configured linter is more important than the degree of the type system. It’s nice to have a strong type system but people forget that a lot of programmers are bad and a good type system won’t change that fact.

>Originally this returned nil when the price information could not be loaded, but a refactoring caused it instead to return 0 which the client happily used.

Hard to feel sympathetic, as this practice violates the Go convention of adding an additional return value to the function to indicate failure, either of type error or bool, as appropriate.

>Go makes it impossible to create a Maybe/Option type

It's very much possible: https://play.golang.org/p/MCxGcZ-rJRU.

Of course, it's not generic, but I have a feeling that might change soon :)

The Option type there isn't type safe. E.g. https://play.golang.org/p/CiQLf4yWhCO doesn't throw a type error for the Get function even though I've omitted the null check.

Sorry, but that's just ridiculous. Obviously the language can't prevent you from defining your Option type incorrectly. The point is that it's not possible to misuse it.

Okay let me rephrase. The type checker doesn't make sure you've checked the value of ok e.g. you can do this: https://play.golang.org/p/x18Rh2iwd2E

Go constantly requires boiler-plate checks for errors, null values etc. without the type checker helping ensure you've checked for an error or null value.

I've never seen those claims about heavy usage of empty interface in the real world, and in the few case we have it, there is type assertion that is safe and well known.

As for the second example I don't think it's a language issue but more a programmer one, how Rust would have saved you in that case, anyone could have returned 0 for the price instead of a proper type. Using Rust doesn't magically turn programmer into good ones. You still have to know how to properly design your code and best use the language and its features.

I'm often reading code in various language and I'm baffled at what a giant lib.rs looks like from someone that never really used Rust.

This is what strikes me: the situation is a programmer being lazy.

They wanted to do: something(getPrice()), but if getPrice can actually fail the then either something needs to accept an error, or they need to handle the error.

No type system imagined can save you from someone who's decided returning 0 is the correct way indicate an error in this scenario.

> how Rust would have saved you in that case, anyone could have returned 0 for the price instead of a proper type

You've missed the problem that was posed. It wasn't returning 0 to indicate an error, it was changing the error value from nil to 0. In rust that would've been a type change (from Option<int> to int). Because the context here was about how stronger type systems (like rust's) allow you to be more specific about your types, and thus many code changes that would not involve the type changing in other more weakly-type languages do cause a type change in rust.

Except that in Go, you always return the error alongside the value, like this:

    return 0, errors.New("unable to get price")

It's less elegant than Options but still, very common practice. GP's company clearly hasn't bought into Go if they're using a library that doesn't follow well-known conventions.

Sounds like your company is just using a unidiomatic library. It's poor practice to return a zero value as an error instead of, well, returning the error. As someone else said, it's standard practice in the vast majority of all go code to return a value, error tuple and check at each call site. In fact, it's so common that it's the number 2 complaint about go code after not having generics (error handling too verbose).

Go has its problems, and it isn't a perfect language, but I have never felt unproductive using it. In fact, my company uses it for all backend services. It has a great stdlib and first class tooling. Most of the discussion in this thread seems to be coming from people who barely use it or have only dabbled with go.

As a tangent, it's really tiring to see HN engage ad nauseum in these pointless language debates. Every language has its place; use it when it's appropriate.

Maybe you need to think why your company is not writing in Rust. Is there some quality of Rust that individual users prefer more than companies in general.

Whenever I hear about Rust in companies same dozen or so companies get mentioned every time.

The specifics of what languages my company writes are mostly historical, and I would say that Rust was not ideal for writing high-throughput network services until this year with the release of async/await.

But in general, companies adopt Go for the same reason they adopt MongoDB [0]: it's really easy to get started with, and get something that "works." The pain comes months or years down the road, and by then you're stuck with it.

[0] A company I previously worked for starting using MongoDB as a small startup, starting finding the limitations about 6 months later, but ending up spending an incredible amount of engineering time over 5 years getting rid of it.

You're a person that really does not like the Go programming language, and that's okay, but to try and paint a perfectly fine tool as bad because someone used it incorrectly, and then compare it to a pretty objectively bad product is silly.

We get it. You don't like Go. Don't use it. That's a perfectly fine option. Plenty of very successful companies, open source projects and services all work with Go (and literally every language) without issue. You not liking something does not make it bad.

And you're welcome to think that. YMMV.

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