Early returns makes the code more linear, reduces conditional/indent depth, and in some cases makes the code faster. In short, it often makes code simpler. The “no early returns” is a soft version of “no gotos”. There are cases where it is not possible to produce good code while following those heuristics. A software engineer should strive to produce the best possible code, not rigidly follow heuristics even when they don’t make sense.

There is an element of taste. Don’t create random early returns if it doesn’t improve the code. But there are many, many cases where it makes the code much more readable and maintainable.

Because good code checks pre conditions and returns early if they are not met.

I remember having this argument with my professor at the school, who insisted that a function should have only one "return" clause at the very end. Even as I tried, I could not get him to explain why this would be valuable and how does this produce better code, so I'm interested on hearing your take on this?

For me it's mostly about indentation / scope depth. So I prefer to have some early exits with precondition checks at the beginning, these are things I don't have to worry about afterwards and I can start with the rest at indentation level "0". The "real" result is at the end.

> Why is "no early returns" not a good rule?

It might be a good guideline.

Its not a good rule because slavishly following results in harder to follow code written to adhere to it.

The "no early returns" rule came about because was a good rule in context, specifically C and FORTRAN code before roughly 1990. It was part of "structured programming", contemporary to "Go To Statement Considered Harmful", Dijkstra, 1968. And it became received wisdom - i.e. a rule that people follow without close examination.

For example of the rule, a function might allocate, do something and then de-allocate again at the end of the block. A second exit point makes it easy to miss that de-allocation, and so introduce memory leaks that only happen sometimes. The code is harder to reason about and the bugs harder to find.

source:

> A problem with early exit is that cleanup statements might not be executed. ... Cleanup must be done at each return site, which is brittle and can easily result in bugs.

https://en.wikipedia.org/wiki/Structured_programming#Early_r...

About 90% of us will now be thinking "but that issue doesn't apply to me at all in $ModernLang. We have GC, using (x) {} blocks, try-finally, or we have deterministic finalisation, etc."

And they're correct. In most modern languages it's fine. The "no early returns" rule does not apply to Java, TypeScript, C#, Rust, Python, etc. Because these languages specifically made early return habitable.

The meta-rule is that some rules persist past the point when they were useful. Understand what a rule is for and then you can say when it applies at all. Rules without reasons make this harder. Some rules have lasted: we typically don't use goto at all any more, just structured wrappers of it such as if-else and foreach

You do realize that there's a handful of literally the same people here on HN continuously evangelizing one technology by constantly dissing on the other? Because of the pervasiveness of such accounts/comments it invites other people, myself included, to counter-argue because most of the time the reality they're trying to portray is misrepresented or many times simply wrong. This is harmful and obviously invites for a flame war so how is that not by the same principle you applied to above account a guideline breach too?

But what’s the relevance of all of this to bird law?

__attribute__((maybe_unused)) or [[maybe_unused]] or such things (dependin on ur spec version i guess?) can be used not to disable a whole line of errors.

I want some defined way to tell the compiler that I am intentionally ignoring the result.

I encounter this when trying to do best-effort logging in a failure path. I call some function to log and error and maybe it fails. If it does, what, exactly, am I going to do about it? Log harder?

Sometimes. For example, you might be setting a non-crucial option on a socket, and if it fails you don't even care to log the fact (maybe the logging would be too expensive), so you just ignore the return value of whatever library is wrapping setsockopt.

there was a recent interview where andrew suggested if i understood correctly: the future path of zig is to make all compilations (successful or not) produce an executable. if theres something egregious like a syntax or type error, the produced artifact just prints the error and returns nonzero. for a "unused parameter", the compiler produces the artifact you expect, but returns nonzero (so it gets caught by CI for example.

> I fail to see how a warning doesn't achieve the same thing while allowing you to iterate faster.

In almost every code base I have worked with where warnings weren't compile errors, there were hundreds of warnings. Therefore it just best to set all warnings as errors and force people to correct them.

> Unless you're working with barbarians who commit code that complies with warnings to your repo and there is 0 discipline to stop them.

I work with a colleague that doesn't compile/run the code before putting up a MR. I informed my manager who did nothing about it after he did it several times (this was after I personally told him he needed to do it and it was unacceptable).

This BTW this happens more often than you would expect. I have read PRs and had to reject them because I read the code and they wouldn't have worked, so I know the person had never actually run the code.

I am quite a tidy programmers, but it difficult for people even to write commit messages that aren't just "fixed bugs".

Go is a very opinionated language. If you don't like K&R indentation, tough - anything else is a syntax error.

It's kind of like the olden days.

You're not supposed to question the wisdom of the Go developers. They had a very good reason for making unused variables be an unconfigurable hard error, and they don't need to rigorously justify it.