But if you are wondering about Error cases, they are there to see when you're looking for them because that ? while unobtrusive is something you can look for.
I'm sure in most IDEs you could have it highlight ? in a "Looking for error handling" mode if that's what you want.
Note that Rust does not consider control flow to be something the core language owns exclusively, you can return core::ops::ControlFlow to say actually I also have an opinion about whether you should keep going, this can make sense for a closure or function intended to be called inside an iterator or other loop context. Some of the ergonomics for this aren't finished, but what is there is already useful where a Result would work but is ugly because your early exit scenario isn't in fact an error at all.
Error handling is no less important than the happy-path.
You just did prove my point though which is that this is the only argument that Go programmers consider, and they blindly reject that adding more lines of code can harm readability.
Can we lower the rhetorical temperature a notch? Just because someone disagrees with you doesn't mean they're "blindly rejecting" your reasoning. In particular, I'm not just a Go programmer--I've used Java, C#, Python, JS, C++, and C in various professional over the course of my career and I've also played around with dozens of other languages and I have more experience with several of those languages than I have with Go. My opinions are shaped by those other languages at least as much as they're shaped by Go, and indeed I didn't start out having these "pro-Go" opinions--rather, I adopted them over time after allowing my preconceptions to be challenged. Note also that some of my preconceptions haven't changed--I still think sum types and enforced handling of return values are a good idea, for example.
This expression
let a = x.iter().filter(...).apply(...).map(...);
for _, v := range x {
if !filter(v) {
continue
}
vv := apply(v, ...)
vm := map(vv, ...)
...
}consider it from a blocks-of-code metric, or some better slightly more abstract metric, that isn't affect by simple things like whitespace transformations, and try assuming that we all understand that we should write code that isn't monstrous to begin with.
I would personally much rather maintain the code in the second example than in the first.
The problem is just that every line creates cognitive load and there's a tradeoff between concision and descriptiveness.
A language with piles of syntactic sugar and magic gets it wrong with too much concision and can read like line noise when it gets overused.
Go goes the other way though and makes it way too verbose and just makes it difficult to read the code. When a method needs to have 6 different error handling clauses in it, then it isn't as clear that 5 of those just bubble up the error while one of them has some unique handling. It also increases the chances that some programmer copypastas the boilerplate bubble-up code to all six of those cases and it sails through PR review. You can write a static analysis linter to force programmers to always handle errors and not ignore them, but you can't force them to handle errors correctly. When humans are reading the code, concision helps and verbosity hurts -- up until that crossover point where magic causes readability to suffer.
Go programmers seem to focus on abhoring magic and rejecting the benefits of concision. But when it comes to PR review your job is to stare at the whole method (or the whole file) and be able to "see" the bug, and more lines of code will make this job more difficult (and is also why some of the recommendations of the "clean code" book are pretty bad since extracting more tiny little methods can harm overall readability). There's a happy optimum somewhere where cognitive load is minimized. That isn't attained though by just having the simplest language design possible and offloading complexity into more verbose code.