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Go is still not good

(blog.habets.se)
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blixt ◴[] No.44983245[source]
I've been using Go more or less in every full-time job I've had since pre-1.0. It's simple for people on the team to pick up the basics, it generally chugs along (I'm rarely worried about updating to latest version of Go), it has most useful things built in, it compiles fast. Concurrency is tricky but if you spend some time with it, it's nice to express data flow in Go. The type system is most of the time very convenient, if sometimes a bit verbose. Just all-around a trusty tool in the belt.

But I can't help but agree with a lot of points in this article. Go was designed by some old-school folks that maybe stuck a bit too hard to their principles, losing sight of the practical conveniences. That said, it's a _feeling_ I have, and maybe Go would be much worse if it had solved all these quirks. To be fair, I see more leniency in fixing quirks in the last few years, like at some point I didn't think we'd ever see generics, or custom iterators, etc.

The points about RAM and portability seem mostly like personal grievances though. If it was better, that would be nice, of course. But the GC in Go is very unlikely to cause issues in most programs even at very large scale, and it's not that hard to debug. And Go runs on most platforms anyone could ever wish to ship their software on.

But yeah the whole error / nil situation still bothers me. I find myself wishing for Result[Ok, Err] and Optional[T] quite often.

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xyzzyz ◴[] No.44983427[source]
Go was designed by some old-school folks that maybe stuck a bit too hard to their principles, losing sight of the practical conveniences.

I'd say that it's entirely the other way around: they stuck to the practical convenience of solving the problem that they had in front of them, quickly, instead of analyzing the problem from the first principles, and solving the problem correctly (or using a solution that was Not Invented Here).

Go's filesystem API is the perfect example. You need to open files? Great, we'll create

  func Open(name string) (*File, error)
function, you can open files now, done. What if the file name is not valid UTF-8, though? Who cares, hasn't happen to me in the first 5 years I used Go.
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nasretdinov ◴[] No.44983477[source]
Note that Go strings can be invalid UTF-8, they dropped panicking on encountering an invalid UTF string before 1.0 I think
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xyzzyz ◴[] No.44983502[source]
This also epitomizes the issue. What's the point of having `string` type at all, if it doesn't allow you to make any extra assumptions about the contents beyond `[]byte`? The answer is that they planned to make conversion to `string` error out when it's invalid UTF-8, and then assume that `string`s are valid UTF-8, but then it caused problems elsewhere, so they dropped it for immediate practical convenience.
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assbuttbuttass ◴[] No.44983745[source]
string is just an immutable []byte. It's actually one of my favorite things about Go that strings can contain invalid utf-8, so you don't end up with the Rust mess of String vs OSString vs PathBuf vs Vec<u8>. It's all just string
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zozbot234 ◴[] No.44984167[source]
Rust &str and String are specifically intended for UTF-8 valid text. If you're working with arbitrary byte sequences, that's what &[u8] and Vec<u8> are for in Rust. It's not a "mess", it's just different from what Golang does.
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maxdamantus ◴[] No.44985383[source]
It's never been clear to me where such a type is actually useful. In what cases do you really need to restrict it to valid UTF-8?

You should always be able to iterate the code points of a string, whether or not it's valid Unicode. The iterator can either silently replace any errors with replacement characters, or denote the errors by returning eg, `Result<char, Utf8Error>`, depending on the use case.

All languages that have tried restricting Unicode afaik have ended up adding workarounds for the fact that real world "text" sometimes has encoding errors and it's often better to just preserve the errors instead of corrupting the data through replacement characters, or just refusing to accept some inputs and crashing the program.

In Rust there's bstr/ByteStr (currently being added to std), awkward having to decide which string type to use.

In Python there's PEP-383/"surrogateescape", which works because Python strings are not guaranteed valid (they're potentially ill-formed UTF-32 sequences, with a range restriction). Awkward figuring out when to actually use it.

In Raku there's UTF8-C8, which is probably the weirdest workaround of all (left as an exercise for the reader to try to understand .. oh, and it also interferes with valid Unicode that's not normalized, because that's another stupid restriction).

Meanwhile the Unicode standard itself specifies Unicode strings as being sequences of code units [0][1], so Go is one of the few modern languages that actually implements Unicode (8-bit) strings. Note that at least two out of the three inventors of Go also basically invented UTF-8.

[0] https://www.unicode.org/versions/Unicode16.0.0/core-spec/cha...

> Unicode string: A code unit sequence containing code units of a particular Unicode encoding form.

[1] https://www.unicode.org/versions/Unicode16.0.0/core-spec/cha...

> Unicode strings need not contain well-formed code unit sequences under all conditions. This is equivalent to saying that a particular Unicode string need not be in a Unicode encoding form.

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xyzzyz ◴[] No.44986105[source]
The way Rust handles this is perfectly fine. String type promises its contents are valid UTF-8. When you create it from array of bytes, you have three options: 1) ::from_utf8, which will force you to handle invalid UTF-8 error, 2) ::from_utf8_lossy, which will replace invalid code points with replacement character code point, and 3) from_utf8_unchecked, which will not do the validity check and is explicitly marked as unsafe.
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maxdamantus ◴[] No.44986537[source]
But there's no option to just construct the string with the invalid bytes. 3) is not for this purpose; it is for when you already know that it is valid.

If you use 3) to create a &str/String from invalid bytes, you can't safely use that string as the standard library is unfortunately designed around the assumption that only valid UTF-8 is stored.

https://doc.rust-lang.org/std/primitive.str.html#invariant

> Constructing a non-UTF-8 string slice is not immediate undefined behavior, but any function called on a string slice may assume that it is valid UTF-8, which means that a non-UTF-8 string slice can lead to undefined behavior down the road.

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adastra22 ◴[] No.44986631[source]
I don’t understand this complaint. (3) sounds like exactly what you are asking for. And yes, doing unsafe thing is unsafe.
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1. maxdamantus ◴[] No.44991964{3}[source]
> I don’t understand this complaint. (3) sounds like exactly what you are asking for. And yes, doing unsafe thing is unsafe

You're meant to use `unsafe` as a way of limiting the scope of reasoning about safety.

Once you construct a `&str` using `from_utf8_unchecked`, you can't safely pass it to any other function without looking at its code and reasoning about whether it's still safe.

Also see the actual documentation: https://doc.rust-lang.org/std/primitive.str.html#method.from...

> Safety: The bytes passed in must be valid UTF-8.