[capableweb]

> Rust has rayon `input.par_iter()`

rayon is a 3rd party library though, not part of the language itself, compared to the Java streams discussed here.

With C# I'm not sure if .NET can be called a library or not? All C# tooling ships with .NET by default or not?

[EnergyAmy]

That's just the way Rust does things, like with the `rand` crate. Lean stdlib, easy dependency management. For the purposes of "does Rust do X", popular crates should be included in that consideration.

[capableweb]

Ok, so then what is this discussion about? Java Streams have existed basically forever, as a 3rd party library, but that doesn't matter here in our conversation about Java language features, where 3rd party libraries somehow changes what the language is...

[EnergyAmy]

I guess it's nice for Java that they did this, but the OP's assertion that no other language handles this as nicely doesn't really stand. For example, this quote:

> In other mature languages, streams are very rigid and feel non-composable

I'd like to see some motivating examples that make me say to myself, "Yeah, Java's got a neat trick there".

[neonsunset]

Whether it ships with it or not is, however, irrelevant. As long as the library is sufficiently popular and accepted by community, it can be seen as the advantage of a particular platform/language.

In this regard, while it is nice that PLINQ and various `Parallel`-related APIs come out of box in C#, it is a marginal difference with Rust where building parallel loops is `cargo add rayon` away.

[samus]

If it doesn't ship with the default distribution of the language, then there's the risk that multiple mutually incompatible libraries emerge or that the adoption by the ecosystem is spotty. Best example: the async runtime mess in the Rust ecosystem.

[neonsunset]

There is no async runtime mess. Tokio is the preferred one, and given Rust's goals it is difficult to do it better (pluggable async executors and the degree of flexibility such abstraction offers - running both on big servers and bare cooperative multi-tasking on microcontrollers).

In addition, multiple versions of transitive dependencies can coexist in Rust without conflicting with each other, there is no such risk.

[samus]

Quite so. But I am under the impression that not every library supports Tokio as a runtime. And while it might be possible to run multiple runtimes in the same process, or use compatibility wrappers, it sounds like trouble.

[pjmlp]

It is definitely a mess, given incompatible semantics making it an herculean effort to write runtime agnostic async libraries.

[capableweb]

> Whether it ships with it or not is, however, irrelevant

When talking about projects in the wild, sure. But if we're specifically talking about language features, then "something being a part of the language" is wildly different than "installable 3rd party library".

[neonsunset]

This mentality is the exact cause behind both .NET and JVM worlds being worse at enjoying the OSS-first benefits of their ecosystems than Rust or, God forbid, Go where it is expected to import a widely known good packages for solving a particular task.

Sometimes, it is a scar tissue from dealing with NIH syndrome too - at least you can use the OOB tools for combating with it, but the NIH itself it the actual source of people being resistant to adopting proven and good solutions developed by community.

[pjmlp]

On the contrary, it means I can be sure wherever there is an implementation the features I depend on are available out of the box, and don't depend on someone during late nights to add support for the given platform.

It also means that I don't need to download the whole Internet for basic features.

[javanonymous]

I'm not sure if I understand your point, but I haven't seen any NIH at the places where I have worked. We have been encouraged to use popular stable libraries when possible.

Java has several 3rd party dependencies that are expected to just be there in projects where I have worked. Examples are Lombok, Apache Commons and SLF4J. These have become so widely used, that I have stopped thinking about them as external dependencies.

Guava used to be more popular too, but now that Java has Optional and Streams, I don't see it as often.

[pjmlp]

It certainly can, if you want to be technical, it is the Base Class Librarily, short BCL.

.NET is the only language ecosystem that is comparable to Java, as they are a kind of yin/yang between themselves.