> Simplify where possible
> eliminate inconsistencies and surprising behavior
Oh dear god please.
> eliminate inconsistencies and surprising behavior
Oh dear god please.
That's exactly what I feel when I read Scala code, everything is a soup of custom operators, implicits and objects disguised like functions (or the opposite, you think it's an object but actually it's a function), it makes the code very hard to maintain and read. At least with Go, Python or Ruby your logic is in plain English, that makes it much easier.
Back in 2010 - 11, when I last worked with it, the compiler was also dog slow and IDE support was terrible. No doubt this has changed for the better, but it did ruin the language for me. I'll stick to Kotlin and Java, thanks.
Secondly, the implicit concept makes the code difficult to read. Then I would add that the differentiation between function & variable isn't always clear and sometimes you don't know what you call.
Yeah, that's what I was talking about - in Scala operators are just functions, and badly named operators are an issue with some libraries rather than an issue with the language. They're unfortunate, but all one can really do is avoid them - no language is impossible to write bad libraries in. Certainly I wouldn't ever want to go back to a language that uses magically-named methods for operator overloading, like Python and Kotlin do - I find that far more confusing, I can never remember whether a * b is calling a.__times__(b) or a.__star__(b) or something else. I could get behind a language that disallowed symbolic names entirely, but I don't think I've seen one of those since Java.
> Secondly, the implicit concept makes the code difficult to read.
IDE support has gotten a lot better now (green underline to highlight any implicit conversion, expand out implicit parameters) which makes them much easier to work with. If you only use implicits in cases where you otherwise wouldn't do anything in code at all, they enhance readability - but of course if you use them to replace things that you'd otherwise make explicit then they can reduce readability. I don't have a good answer, because I definitely want extension methods, typeclasses with derivation, and the magnet pattern, but I haven't yet seen a language design that makes those things possible while disallowing the bad uses of implicits.
Want to add a value to a (mutable) Seq? Use +=.
Want to add a value and return a new Vector? Use +.
Want to build a new list that is the concatenation of two Lists? Use ++.
sbt is probably where you encountered "weird" operators, but their use has declined over the past few years from what I've seen.
https://github.com/foursquare/fsqio/issues/37
They don't upgrade the open source version because their internal version depends on that open source version and they don't can't upgrade internally to 2.12.
They can't upgrade because of several dependencies of their own, the last one Finagle.
All of those although "cross compiles are no problem" as the default answer from the Scala development team on these issues.
There are Many people who work at many companies doing real development with Scala that goes all the way to production, handling real user traffic.
But I wonder how many companies would make the same decision again after their experience with Scala.
I assume that the "added feature" section of the Dotty documentation and this blog entry have been written by different persons, because it's utterly impossible to reconcile those documents:
More complicated features, more experiments, more NIH, more ad-hoc inventions, larger language footprint with more inconsistencies and surprising behaviors.
I wouldn't want to have any more language features that pushed as hard as implicits do, but one somewhat-experimental feature in a language is ok, just about. I don't think Scala is a thousand-year language, but it strikes the best balance given the current state of the art.
Extension methods: too much potential for confusion
Magnet pattern: no idea what that is
Personally I feel OCaml strikes the best balance :-) But we may be arguing about an inch here rather than a mile.
If you don't like them, why don't you add "Use of implicits forbidden" to your coding style guidelines, and check in code-reviews, and add a "grep implicit" check to your CI setup that refuses to commit Scala code with implicits?
Let me paraphrase M. Odersky's PLDI 2017 keynote:
The essence of Scala is implicits
Because Scala libraries that do useful stuff are infested with them. Akka loves the things.
> main complaint
They obscure complexity, pretending that complex stuff is simple. It makes simple stuff trivial but complex stuff harder.
So? Treat Akka as a black box. You can always explicitly pass implicit arguments.
Only someone who has never worked in a team before would suggest this.