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0 pointsTheDong7y ago0 comments

I don't understand.

Go errors out on unused imports, but you can type "import _ foo.com/unused-import" to not error out.

Why doesn't 'errors.New("asdf")' error out and require you to instead write '_ = errors.New("asdf")' to ignore the result

I think the real answer is not that it's intentional design, but rather that the original compiler was not powerful enough to implement that feature easily... and once go hit 1., it was impossible for them to add new warnings or errors because there are no warnings and errors are backwards incompatible.

Sure, that means developers use third-party tools for warnings because the go compiler refuses to ever have warnings (that compromises the pure beauty of the language obviously), but at least that means it's only the users that have to deal with the complexity of using more tools, the compiler developers can ignore it.

0 comments

mopsy7y ago

I don't think it's because of the complexity. I'm quite sure it would not have been difficult to do.

One of the reason is that you don't always want to check the error. The most common one is fmt.Println.

I would not like to always write

_, _ = fmt.Println("Hello, playground")

stubish7y ago

You certainly do not always want to write _,_ = fmt.Println("Hello, playground"), and I think this points out the real lack. What do you want your program to do if fmt.Println starts failing? I think, unless you are explicitly checking for errors, that in all other cases you want it to crash. Rather than silently continue. Which is a bug, and a potentially disastrous one, that is endemic in Go code (and, to be fair, plenty of other languages). Thankfully the practical risk of this particular case is tiny.

This is why you want unchecked errors to implicitly bubble up. Which is what exceptions give you, or perhaps a syntax with implicit error return values rather than Go's by-convention approach.

pstuart7y ago

If fmt.Println fails you've likely got bigger problems and the game is over.

And if it means a lot in this case, wrap the function and use it instead.

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