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Comment by californical | Hacker News Reader

It's interesting that you say this, because I've had the opposite experience. I wouldn't say it's strictly inferior, because there are definitely upsides. If it was strictly inferior, why would a modern language be designed that way -- there must be some debate right?

I love multiple returns/errors. I find that I never mistakenly forget to handle an error when the program won't compile because I forgot about the second return value.

I don't use go at work though, I use a language with lots of throw'ing exceptions, and I regularly miss handling exceptions that are hidden in dependencies. This isn't the end of the world in our case, but I prefer to be more explicit.

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> If it was strictly inferior, why would a modern language be designed that way

golang is not a modern language (how old it is is irrelevent), and the people who designed it did not have a proper language design background (their other accomplishments are a different matter).

Having worked on larger golang code bases, and I've seen several times where errors are either ignored or overwritten accidentally. It's just bad language design.

I cannot think of a language where errors cannot be ignored. In go it is easy to ignore them, but they stick out and can be marked by static analysis. The problems you describe are not solved at the language level, but by giving programmers enough time and incentives to write durable code.

The following line in golang ignores the error:

    fmt.Println("foo")

Compare to a language with exception handling where an exception will get thrown and bubbles up the stack until it either hits a handler, or crashes the program with a stack trace.

And I was referring to accidental ignoring. I've seen variations of the following several times now:

    res, err := foo("foo")
    if err != nil { ... }
    if res != nil { ... }
    res, err = foo("bar")
    if res != nil { ... }

Usage of linters fixes this:

>The following line in golang ignores the error:

   fmt.Println("foo")

fmt.Println() is blacklisted for obvious reasons, but this:

    a := func() error {
        return nil 
    }
    a()

results in:

    go-lint: Error return value of 'a' is not checked (errcheck)

>And I was referring to accidental ignoring. I've seen variations of the following several times now:

    res, err := foo("foo")
    if err != nil { ... }
    if res != nil { ... }
    res, err = foo("bar")
    if res != nil { ... }

results in:

    go-lint: ineffectual assignment to 'err' (ineffassign)

> fmt.Println() is blacklisted for obvious reasons

That's the issue with the language, there are so many special cases for convenience sake, not for correctness sake. It's obvious why it's excluded, but it doesn't make it correct. Do you want critical software written in such a language?

Furthermore, does that linter work with something like gorm (https://gorm.io/) and its way of handling errors? It's extremely easy to mis-handle errors with it. It's even a widely used library.

Huh, I have seen enough catch blocks in Java code at work which are totally empty. How is that better than ignoring error?

Because it's an explicit opt-in, as opposed to accidental opt out. And static checking can warn you about empty catch blocks.

In rust, errors are difficult to ignore (you need to either allow compiler warnings, which AFAICT nobody sane does, or write something like `let _ = my_fallible_function();` which makes the intent to ignore the error explicit).

Perhaps more fundamental: it’s impossible to accidentally use an uninitialized “success” return value when the function actually failed, which is easy to do in C, C++, Go, etc.

Or .unwrap(), which I see relatively often.

That’s not ignoring errors, it’s explicitly choosing what to do in case of one (crash).

Error handling is hard, period. Error handling in go is no worse than any other language, and in most ways it is better being explicit and non-magic.

> people who designed it did not have a proper language design background

Irrelevant.

> It's just bad language design.

try { ... } catch(Exception ex) { ... }

Exceptions don't lead to silent but dangerous and hard to debug errors. The program fails if exception is not handled.

> try { ... } catch(Exception ex) { ... }

The error here is explicitly handled, and cannot be accidentally ignored. Unlike golang where it's quite easy for errors to go ignored accidentally.

Nevertheless, this is how it is mostly done in Java. I haven't used eclipse in eons, but last time I did it even generated this code.

If you care with go, use errcheck.

Does errcheck work well with gorm (https://gorm.io/) and it's way of returning errors? This is not an obscure library, it's quite widely used.

Does any language save you from explicitly screwing up error handling? Gorm is doing the Go equivalent of:

     class Query {
         class QueryResult {
             Exception error;
             Value result;
         }
         public QueryResult query() {
             try {
                 return doThing();
             } catch(Exception e){
                 return new QueryResult(error, null);
             }
         }
     }

Gorm is going out of its way to make error handling suck.

> Does any language save you from explicitly screwing up error handling?

It's about the default error handling method being sane. In exception based languages, an unhandled error bubbles up until it reaches a handler, or it crashes the program with a stacktrace.

Compare to what golang does, it's somewhat easy to accidentally ignore or overwrite errors. This leads to silent corruption of state, much worse than crashing the program outright.

> It's about the default error handling method being sane.

Gorm isn't using the default error handling.

That's one point in this discussion. The language allows error handling that way. Compared to a language with proper sum types or exceptions, where one would have to actively work against the language to end up with that mess.

> That's one point in this discussion. The language allows error handling that way. Compared to a language with proper sum types or exceptions, where one would have to actively work against the language to end up with that mess.

I've seen a bunch of code that does the equivalent of the Java I posted above. Mostly when sending errors across the network.

because it has try/catch. Without that (which would be similar to not checking the err in go) it explodes or throws to a layer up that may not expect it.

Each language has its wonks.

> Without that (which would be similar to not checking the err in go) it explodes or throws to a layer up that may not expect it.

It's not similar to that at all. Without it, the exception bubbles up until it gets caught somewhere, or crashes the program with a useful stacktrace.

With golang, it just goes undetected, and the code keeps running with corrupt state, without anyone knowing any better.

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