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Comment by pipe_connector | Hacker News Reader

If I'm reading your feedback correctly it sounds like you want:

1) Syntactic sugar for if err != nil { return err }; similar to ? in Rust

2) The errcheck linter to be enforced (part of go vet, maybe?)

3) Exhaustive switch statements

The first point was looked at and no one has proposed a solution enough of the community could agree was an improvement while maintaining sufficient explicitness. If someone has a really good proposal for this I am sure it would be considered.

The second point could probably happen with enough lobbying. So, verbosity is still there but at least every project will do something with their errors.

The third point I don't believe is possible today because of the way interfaces work. If Go added sum types then this should be possible, but I could be mistaken about that.

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1) Yes I didn't want to make the tired comparisons to Rust but Rust does have the excellent syntactic sugar for returning errors. Of course, something like this is hampered by the lack of sum types and the ambiguous zero values in Go which makes it more difficult for the compiler to know what to return but I hope we eventually get there or we find another way to do this

2) I'm not a fan of leaving error checking to linting. It would be fantastic if the compiler would stop for mishandled errors. It already doesn't compile for banal things like unused imports and variables

3) It's not really a matter of wanting exhaustive switch statements as such but if this was present, it would make error handling much simpler, again a la Rust (I'm sorry)

These are all hopes and wishes to make the language better to work with and I'm sure if we get anything close to any of this, it would be a while. The Go governance seems to move very slowly and deliberately considering how long it took them to wake up to adding generics but we can still dream

> > Syntactic sugar for if err != nil { return err }; similar to ? in Rust

> Yes I didn't want to make the tired comparisons to Rust but Rust does have the excellent syntactic sugar for returning errors.

Many people seem to forget that Rust didn't start (even in its 1.0 release) with the ? operator. It started with the try!() macro, which expanded to something not unlike Go's "if err != nil { return err }". The ? operator was added later, as a shortcut to the same semantics as the macro except for also being able to work with Option instead of just Result, based on developer experience with the macro (the two major annoyances being not being able to use the macro with Option, and the nesting when chaining several uses of the macro).

If Rust was able to create the ? operator based on developer experience with its try!() macro, I don't see why Go won't be able to create its own error propagation operator based on developer experience with its "if err != nil { return err }" idioms.

> If Rust was able to create the ? operator based on developer experience with its try!() macro, I don't see why Go won't be able to create its own error propagation operator based on developer experience with its "if err != nil { return err }" idioms.

Because Go does not have declarative macros. So while Rust got something like 25 versions out of try! before considering that it’s worth an operator (but it could well have gone with an other pattern if one had arisen) that’s not really an option for go.

> 1) Syntactic sugar for if err != nil { return err }; similar to ? in Rust

IMO they could exactly use what you wrote, ie. change gofmt to have it all on one line like that. The biggest annoyance with the error return boilerplate is the waste of vertical space and just squashing it into 1 line would fix that.

Or perhaps allow variable assignment to be used in the same scope.

if x, err := someMethod(); err != nil { return err }

x <- is usable here.

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