| I seem to be missing the point of your argument. > I think this is the fundamental point of contention. I agree with your point. Part of Go was definitely the removal of unnecessary abstraction and complication. However my argument is that they went too far. > Go aims at abstraction at the package level [...] Rust seems to aim at abstraction at the line level I don't understand the difference in your mind vs package level or line level. For whatever is exposed as a package is surely intended to be used in a line elsewhere in the program. > On the other hand, Rust has .iter(), .map(), .filter_ok() and .collect(). So, while I think anyone could understand the Go code if you explained `range` to them If you explain range, continue, return and append then you could understand the Go snippet. I don't see how this is meaningfully different from explaining iter, map, filter_ok and collect. Sure, the former are language features while the latter are library features but that doesn't seem to be a meaningful difference when it comes to comprehension. > Yes, I understand what it does, but I have no clue how it does it. This is the whole point of my argument. You don't need to understand how it works. Much like you don't need to understand how continue or append work in go. That is the point of abstraction. You need to know what they do, not how they do it. In my opinion Go forces you to leave too much of this usually-irrelevant plumbing in the code, which distracts from the interesting bits. > The way Go deals with complexity is by eliminating it This is again my key point. I'm arguing that in most cases Go hasn't managed to eliminate the complexity. Maybe it got rid of a little, as your "map" loop doesn't need to be as generic and perfect as the Iterator::map in the standard library. But the complexity that is left is now scattered around your codebase, instead of organized and maintained in the standard library. The intrinsic complexity has to live somewhere. And in Go I find a lot more lives inline in your code. In other languages I find it is much easier to move the repetitive, boilerplate elsewhere. And when this is done well, it makes the code much, much easier to read and modify as well as leading to more correct code on average. > That's a Go feature. I agree with that. But what I am trying to express that in my experience this is actually a flaw. It looks good at the beginning. But once you start reviewing code you start to see it break down. I think Go had a great idea, but based on my experience I don't think it worked out. |
Absolutely. The difference is that Go has a limited number of such features and once you have learnt them that's all you need to know, in that sense, and can understand any code base.
One thing which I have not expressed very well in my reply is what exactly I meant by "understanding what the code does". When you look at func fetchData(T1) (T2, error), it's easy to understand what it does: it fetches some data from T1 and returns it as T2, with the possibility of it failing, and returning an error. If you know what T1 and T2 are (which you should if you're inspecting that code), that's usually sufficient. You understand (almost) all of it's observable behavior, which is different from it's implementation details. Similarly, `abs` returns the absolute value of a number
`append` also has easy to understand observable behavior: it appends the elements starting at position len(slice) and reallocating it if necessary (generally, if the capacity is not big enough), but it's actual implementation is undoubtedly very complex. `range` is harder to explain, but rather intuitive when you get the hang of it.
Of course you also want to keep in mind the behavior of all the language primitives as well: operators, control flow etc. In Go, you have to keep all of these things in your head to understand what is happening in the code, but once you do you really understand it.
We can call all of these things: variables, language primitives, API functions etc. atoms of behavior. In Go, to understand a piece of code, you first have to understand what the observable behavior (but usually not the implementation) of all of the atoms in that code are, and then understand all of the interactions between those atoms that happen as a result of programmer instructions.
What I mean by line-level vs package-level abstraction is quite simple (maybe not the best names, but hey, I'll stick with them). With package-level abstraction, the atoms, as well as the interactions between them, remain conceptually easy to understand, but become more powerful as you move up the import tree. The observable behavior of an HTTPS GET is easy to understand, but very complex under the hood.
With line-level abstractions the atoms, and especially the interactions between them, become very complex. The programmer no longer "has to understand" the observable behavior of every single function he uses. Odd one-off mutators are preferred to inlining the mutation because it "makes the code more expressive" - in that it makes it look more like english, it makes it easier to understand what the programmer is trying to do. It does not, however, make it easier to understand what the programmer is actually doing, because the number of atoms - and their complexity - increases substantially. If you want to get a feel for this look at the explanation for any complex feature in C++ on cppreference.com. I must have read the page on rvalue references 20 times by now and I still don't grok it.
Of course, with line-level abstraction, the programmer doesn't need to constantly keep in mind 100% of the behavior of the atoms he's using, much less whoever's reading.
I can't tell you which one's better - probably both have their place - all I'm saying is that I, personally, can't work with C++/Rust/other languages in that style. I've tried to use them but I can't. C is easier to use - for me.