[oneepic]

With this the language gets a little more beautiful. On a related note, I just switched from a C# job at Microsoft (microservices) and moved to a Java shop where we're all really just starting to learn Kotlin and migrate our work there. I'm shocked how many times we've learned a fancy feature and I get to say, "actually, C# has something just like this too." (i.e. operator overloading) It is a surprisingly modern language keeping up with the other ones.

[moritonal]

Err.. I'm too drunk to check, bit I'm fairly sure C# has had operator overloading for like ten years?

Having worked recently in it, I found Java to be relatively (as a language, not for tooling) backwards compared to C#.

[nathanaldensr]

C# has supported operator overloading since C# 1.0 in 2002. See section 7.2.2 of the original specification.

[nkozyra]

I think that's what the poster you're replying to is saying.

[oneepic]

No, the reply raises a valid issue. I was implying that op overloading was a modern thing, but it's apparently been around for a very long time, and doesn't seem to be the best example of a "modern" feature of languages.

[thrower123]

C++ had operator overloading in the 90s. Mostly we decided it was a bad idea.

Every generation must learn this for themselves though.

[dgrunwald]

Operator overloading has been traditionally overused, especially in C++ (shift operators for iostreams, C++ iterators). Java was the peak of the push-back against that. C# has operator overloading, but forbids many things that were possible in C++:

  * `operator=` and `operator ,`
  * `operator new` and `operator delete`
  * `operator +=` overloaded differently from `operator +`
  * `operator &&` and `operator ||` overloading works differently in C#, so that it preserves the short-circuiting behavior
  * `operator ++` only can be overloaded once in C#, with the compiler automatically handling the difference between pre- and post-increment

But more crucially, the C# standard library uses operator overloading only for types like `decimal` and `BigInteger`. C# programmers can go years without ever overloading an operator, while still profiting from it whenever they use `BigInteger`. It's very different from the C++ culture where

  * everyone needs to learn about how to overload `operator=` (for memory management)
  * the standard library encourage abuses of operator overloading such as shift operators for iostreams

It should be unsurprising novice programmers abuse operator overloading when the C++ language teaches them exactly that.

[Guvante]

Except C++ didn't learn that operator overloading is bad. C++ learned that operator overloading for everything was bad.

The language kind of put itself into a corner when what C# calls `MoveNext` is called `++` (with two variants of course) and what C# calls `Current` is called `*`. Taking what mathematically worked for iterating an array and taking it piecemeal to define your syntax is the kind of operator overloading that is a bad idea.

[zerkten]

People don't appreciate how much of an impact C++ had on C#. People consider it a Java clone, but the first version had many features to support a large segment of C++ (COM) developers that Microsoft wanted to move to .NET. This brought a visible performance hubbub at the time which was often instigated by the folks more comfortable with C++, manual memory management, etc.

[pjmlp]

You are missing the part where Java's clone done by Microsoft, J++ already had those features, and it was the first project Anders worked at Microsoft, hence it also has the property/event ideas from Delphi, and a framework that was the predecessor of Windows Forms.

These were the major pain points for the Java lawsuit that Sun did against Microsoft.

The irony with all these attempts to make COM easier to use is that they always fail flat when the Windows dev team has their turn, and then they undo everything and we are back into C++ and IDL land (latest version of it, C++/WinRT).

[thaumasiotes]

Python has operator overloading now. (And as far as I know, always has.) Avoiding operator overloading was one of several weird, idiosyncratic decisions Java made.

[naasking]

Operator overloading in a language in which memory management is all manual would be more challenging. That doesn't really tell us about its suitability in a language with automatic memory management. We've had about 20 years of C# with operator overloading, and it's been totally fine.

[FpUser]

>"Mostly we decided it was a bad idea."

We who? From where I stand people are fine with operator overloading where it makes sense and C++ is far from being the only language with this feature.

Problem comes when shitty programmers get orgasmic about some language feature and try to use it everywhere to everyone's detriment.

[spaetzleesser]

You have to have real good taste to use operator overloading. Often it just leads to obfuscated code where the operators have weird behavior. Extension methods are also way overused. I have had numerous occasions where I thought the .NET framework was buggy only find out that it was somebody’s badly written extension method causing problems.

[FpUser]

>"You have to have real good taste"

Gross exaggeration. Just a bit of plain common sense. Do override operators to perform matrix ops. Do not override + operator to do multiplication instead. And do not subtract apples from cars.

As for your further example as I said give shitty programmer code in any language and they will manage to fuck it up.

[thinkharderdev]

I think you and the parent are saying basically the same thing. I've been working in Scala for the past 10ish years and we have definitely gone through the "hype cycle" of operator overloading. Early Scala libs went a little nuts with creating an incredible array of symbolic operators (most famously this atrocity http://www.flotsam.nl/dispatch-periodic-table.html). We collectively realized that this was overboard and now Scala libraries typically provide a more modest set of symbolic operators (and generally the symbolic operators are just aliases for named methods so you can decide which ones you want to use in any particular codebase).

I would also disagree with the characterization as shitty code. The operators are actually really nice if you manage to learn them all well. It can make the code both very concise and readable. But it optimized for people who know the libraries extremely well over people who don't, which usually is not a great tradeoff for widely used libraries.

[krisrm]

I thought we just decided C++ was a bad idea? :) (shhh, nobody tell the games guys)

[memco]

I only know two or three game devs but they all use C++ spitefully because there isn’t any better options to them at the moment. They’re all itching for something better and there are lots of options that are becoming viable so maybe C++ won’t be the only game in town.

[dpratt]

You’re going to love Kotlin, it really is a fantastic pragmatic language.

You’re also likely to discover that while C# the language is amazing, the CLR runtime looks frankly minor league when compared to the JVM.

[creato]

> the CLR runtime looks frankly minor league when compared to the JVM.

This is comically backwards from my experience. I often see near-native optimized performance on C#/CLR, where I see similar code (SIMD friendly loops) literally hundreds if not thousands of times slower than it should be in Java.

[jpgvm]

See my longer reply but I think this basically comes down to it being much easier to write fast C#. Generally if you are experienced enough with Java you can make it do what you want and get to the same performance (or higher) with Java but it's definitely not as easy and I do think this is a serious downside to Java.

[_old_dude_]

Very true, Java was late in the game in term of SIMD loop optimizations compared to C#.

Oracle engineers did the first implementation for Java 7, more recently it's mostly contributions from Intel, AMD and ARM [1].

[1] https://cr.openjdk.java.net/~vlivanov/talks/2019_CodeOne_MTE...

[pjmlp]

Which Java?

OpenJDK, GraalVM, Open J9, Aicas, PTC, microEJ, Azul, Amazon,....

[jbjbjbjb]

What is better in the JVM?

[jpgvm]

I think both have different pros.

Java has higher peak JIT performance though after Rosalyn was introduced C# has made strides at closing that gap on many metrics. GC algorithms are more advanced, namely ZGC and Shenandoah. I would elaborate but I don't want to turn this post into an actual essay. JVM is more configurable. This is a double edged sword, it heavily favors users that have spent the time to really understand the platform but it has created a reputation of the JVM being hard to operate. JVM class loaders and the new(ish) Jigzaw module system are very powerful, especially for shipping customized/cut-down JVM + stdlib when you need to do distribution. JVM has better portability. .NET Core has obviously changed the game but other platforms are still treated second class to Windows in many ways. GraalVM is reviving the guest language ecosystem of the JVM. Clojure, Scala and Kotlin have all remained reasonably strong but there was a dark period there for Jython/JRuby and friends. GraalVM is changing the tide here and I have already been able to leverage this over Nashorn to embed essentially native speed JS code into one of my Java programs.

CLR has better primitive types, JVM's project Vahalla may resolve this. The CLR/.NET tends to introduce features at a quicker pace than the JVM/Java, this I feel is CLR's double edged sword. Async/await being the key example. It's been in the CLR for what feels like forever now vs JVM which is only now just getting close to landing Loom. However I feel like Loom is an infinitely better solution to the problem that leverages the unique advantages of JIT compiled VM languages that rely on relatively little unmanaged code. The experience on the CLR is much more integrated assuming you are on the well trodden path. i.e VS + Windows 10. MSIL is much much more pleasant than JVM bytecode in my experience and the community developed tooling for working with it is great. Optimizing programs on CLR is easier than JVM, it takes comparatively less effort to write allocation free code and get great memory layout using primitive arrays etc for high performance code. CLR interacts better with native code. JNI is poor in comparison. Project Panama could make this better on the JVM side.

This is by no means a complete list of ways the two differ, this is just my experiences having written a decent chunk of code for both.

FWIW I prefer the JVM but if I am forced not to use the JVM the CLR is the very next thing I propose.

[rndgermandude]

>.NET Core has obviously changed the game but other platforms are still treated second class to Windows in many ways.

Not really. Maybe a tiny little bit, but not really. Microsoft has discovered that the "other platforms" are very important, because they want to sell Azure, and people there will use linux predominantly. Same as MS invested heavily in WSL to support "linux" workflows.

dotnet on linux might not be completely to parity with dotnet on windows when it comes to platform integration, but it's getting there. dotnet on macos is somewhat similar in this regard and maybe a little bit slower to catch up because may be a little lower in priority than linux.

Anyway, it's not my impression that platforms other than Windows are treated second class. It's just that Microsoft has already invested decades in the Windows implementation, while the linux and macos implementations are rather fresh (although dotnet using mono as a base certainly helped) and therefore less optimized yet in certain regards.

>Java has higher peak JIT performance though after Rosalyn was introduced C# has made strides at closing that gap on many metrics.

That isn't really true. JIT (peak) performance is pretty much comparable between Java and dotnet, maybe even a little better in dotnet/RyuJIT. There are certain areas where one is better than the other.

Roslyn is the C# to MSIL compiler, btw, while the JIT compiler for MSIL is RyuJIT. While Roslyn helps produce MSIL that is (hopefully) great to JIT compile, the actual JIT compilation work happens in RyuJIT.

> GC algorithms are more advanced, namely ZGC and Shenandoah.

Yes, GC is where the JVM really shines - if you go through the trouble of finetuning it to your particular need. At the same time the CLR GC seems to work better by default, but it's a lot less configurable too. In the CLR you basically have only 3 modes of operation: interactive GC (concurrent, trying to avoid GC pauses, with the trade off of less performance, for things like GUI applications), non-concurrent GC (which works well for a lot of CLI type tools and some services, where small GC pauses are less noticeable), and "server" (which is e.g. a lot less eager to "return" memory to the OS, aimed at long running processes that are then usually the only major thing running), and that's basically it, where on java you have tons of available schemes/algorithms and each one is usually heavily configurable as well.

As you already hinted at, dotnet made great strides in the last years to avoid a lot of heap allocations and the GC with value types, Span<> and friends, avoiding boxing a lot of times and bringing stackalloc to managed code, and their use in the standard library. So peak GC performance is a little less important in the CLR than in the JVM (but still very important, of course).

You say "may" a lot, referring to proposed java changes e.g. to add value types, make native code interaction less painful, add some form of async-await. Great. And I hope they will finish up and ship these things eventually, and it will be great implementations. The thing is dotnet already has all these things shipped and in production already, often for quite a while. And while java is still figuring out the design, dotnet can already improve their shipped implementations based on real world experience and data in every new version, and usually does so. Java/JVM is playing catch up here.

>Async/await being the key example. It's been in the CLR for what feels like forever now vs JVM which is only now just getting close to landing Loom. However I feel like Loom is an infinitely better solution to the problem that leverages the unique advantages of JIT compiled VM languages that rely on relatively little unmanaged code.

From what I have seen of Loom so far (which is admittedly not that much) my impression is the direct opposite. To me it so far looks worse conceptually and API-wise than what MS did, while still borrowing a lot of general async-await concepts and even C# and CLR specific concepts, but worse. Don't get me wrong, C# async-await and the CLR support for it has a lot of problematic areas too and is far from perfect and easy, aside from general async-await conceptual problems, but it doesn't seem to me like Loom is avoiding or solving those things, instead adding quite a few of their own warts on top. But as I said, my exposure to Loom is very limited, and it's not a final product yet anyways, so I may be very wrong here.

Loom reminds me of when Java tried to copy a lot of collections-based LINQ stuff but did a terrible job doing so in my humble opinion (they since fixed some of the worst mistakes). Or maybe I am just biased, which is certainly a possibility.

[5e92cb50239222b]

> Microsoft has discovered that the "other platforms" are very important

Very important to be able to run applications, not to develop them. I spent a few years doing dotnet development on Linux and have had enough of it (so I'm moving away to JVM which looks more and more interesting as long-term research projects and some language improvements land). It is very much a second class citizen. They still want to force developers use Windows and their tooling.

[torginus]

This hasn't been my experience tbh. Sure, VS doesn't exist on Linux, but VS isn't the best .NET dev environment (even with Resharper), Jetbrains' Rider is, and I haven't felt like the experience is any different on Linux, compared to Windows. The command line tooling introduced with .NET Core is excellent, I usually prefer it to clicking around in a GUI, and it works perfectly on Linux. VS Code also has full .NET support, and uses the same autocomplete engine as VS does. Imo it's not as good as Rider, but not worse than the support for other languages, like Go where it's my go-to editor.

[dgellow]

Would you mind going more into details? Jetbrain’s IDE + dotnet CLI offers a very compelling experience on both macOS and Linux.

[rad_gruchalski]

The ecosystem.

[spaetzleesser]

That’s very important. This is the reason why I would use Java over .NET for new code. MS is making a big mistake not providing means to call Java from .NET. There was a library called KVM but I think it has been abandoned.

[dgellow]

What is missing in the .Net world?