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Comment by MrBuddyCasino | Hacker News Reader

Also, no plans to get rid of implicits apparently. Sorry Scala, we're not gonna be friends.

Not fully, but implicit type conversion must be marked explicitly: https://medium.com/bigdatarepublic/key-takeaways-from-the-sc...

Here's the current state: https://github.com/lampepfl/dotty/pull/4229

Implicits are very powerful when used correctly, but are terrible if not.

If "<feature> is very powerful when used correctly, but terrible if not": think long and hard before adding to a language.

Completely agreed. Implicits are the one place where Scala genuinely pushes the art of language design a bit beyond what's really possible; I expect future languages to come up with a better solution to the same problem. But in the meantime the things they enable - typeclasses, extension methods, the magnet pattern - are too valuable to do without, and we can't just sit around and wait for the perfect language to arrive.

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.

Typeclasses: barely workable–if the implementor knows how to save the caller from paying the 'import tax'

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.

which is why I'd be against adding them in Java and favor keeping the power in scala.

What is your main complaint with implicits?

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

You can find it at https://www.youtube.com/watch?v=br6035SKu-0

> 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?

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.

> Akka loves the things.

So? Treat Akka as a black box. You can always explicitly pass implicit arguments.

"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?"

Only someone who has never worked in a team before would suggest this.

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