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IT Runs on Java 8

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Re: IT Runs on Java 8

#391

Post by [deleted] »

pron wrote: post #372
sporkland wrote: post #348

Earlier quoted context omitted.

Dumb question. Why do reified generics make interop challenging? Or is it reified generics plus value types that don't inherit system.Object? Couldn't the language implementations basically pass around ICollection in .NET somewhat similar to how they do in Java?

> Why do reified generics make interop challenging? Suppose you have types A and B, such that A and List ? This question is called variance, and different languages have very different answers to this, but once generics are reified, the chosen variance strategy is baked into the runtime. > Couldn't the language implementations basically pass around ICollection in .NET somewhat similar to how they do in Java? They cou…

[deleted]

Re: IT Runs on Java 8

#392

Post by bunderbunder »

munchbunny wrote: post #362
sporkland wrote: post #348

Earlier quoted context omitted.

Dumb question. Why do reified generics make interop challenging? Or is it reified generics plus value types that don't inherit system.Object? Couldn't the language implementations basically pass around ICollection in .NET somewhat similar to how they do in Java?

The problem is that your GenericClass and GenericClass are really more like GenericClass_T1 and GenericClass_T2 with their own distinct type definitions and interfaces. From the perspective of a different runtime/language trying to interop with these types, you have to somehow understand and work with this mapping game. It's much easier from inside the .NET runtime than outside. The general solution is, like you sugg…

The solution I remember from the last time I dealt with Python on .NET (which was admittedly a long time ago) was the opposite - you did use the reified generics, and there were facilities to create an instance of GenericClass from within Python. There's a whole dynamic language runtime that is purpose-built for smoothing over a lot of that stuff.

What wouldn't work would be to, e.g., create a Python-native list and try to pass it into a function that expects a .NET IList. Which doesn't feel that odd to me - they may have the same name, but otherwise they're very different types that have very different interfaces.

That said, the Iron languages never took off. My personal story there is that all the new dynamic features that C# got with the release of the DLR pretty much killed my desire to interact with C# from a dynamic language. The release that gave me Python on .NET also turned C# itself into an acceptable enough Python for my needs.

Re: IT Runs on Java 8

#393

Post by yourbandsucks »

wildermuthn wrote: post #183
dcole2929 wrote: post #49

In the majority of companies it's simply not possible to operate on the bleeding edge the way HN articles would have you believe you should. Besides the obvious issues around the value of rewriting stable legacy systems on new platforms, there are also man power issues. You need tier 1 developers to live on the bleeding edge because any problem that comes up (and they will come up) largely requires you to solve it yo…

Good points here. Which is why HN is oriented toward startups with Tier 1 engineers. PG and his cofounders invented the web app, using a combination of old tech (lisp) and new (the internet). There are plenty of other forums and sites to read about conventional tech. HN is where I find the bleeding edge. 90% of it is just fascinating. But the other 10% offer tantalizing possibilities for making something novel, which…

Oh, for christ's sake. I don't want to get all "get off my lawn" but HN is full of early-20-somethings rediscovering things and calling them 'bleeding edge'.

The highest paid people in our industry are working on drudgery full-time for FAANG. And that's fine, people have families, I'm not judging anyone. But let's not fool ourselves.

Re: IT Runs on Java 8

#394

Post by bunderbunder »

pron wrote: post #372
sporkland wrote: post #348

Earlier quoted context omitted.

Dumb question. Why do reified generics make interop challenging? Or is it reified generics plus value types that don't inherit system.Object? Couldn't the language implementations basically pass around ICollection in .NET somewhat similar to how they do in Java?

> Why do reified generics make interop challenging? Suppose you have types A and B, such that A and List ? This question is called variance, and different languages have very different answers to this, but once generics are reified, the chosen variance strategy is baked into the runtime. > Couldn't the language implementations basically pass around ICollection in .NET somewhat similar to how they do in Java? They cou…

> This question is called variance, and different languages have very different answers to this, but once generics are reified, the chosen variance strategy is baked into the runtime.

Which, realistically, is probably the only principled way to do things if you want to be doing much with variant generics in a cross-language way.

The Java way, "I pick my variance strategy, you pick yours, and we'll both pass everything around as a List at runtime and just hope that our varying decisions about what their actual contents are allowed to be never cause us any nasty surprises for each other at run time," is not type-safe and can lead to nasty surprises at run time. It's easier, sure, but easier is not necessarily better.

Re: IT Runs on Java 8

#395

Post by whatshisface »

geofft wrote: post #64
mzkply wrote: post #44

The HN front page is similar to any community. For example, a car site's homepage will be listing the latest supercars, expensive turbos, rims, whatever... while most readers are driving a $30,000 Civic. The best & brightest in tech are working with the best tools on the biggest problems, and that's what gets talked about, regardless of what the mass is doing.

> The best & brightest in tech are working with the best tools on the biggest problems I don't think that's true—there is a subset of the best and brightest who work on greenfield projects very decoupled from existing customer bases, and they get to blog / present / post a lot about what they're doing. There are quite a few "best and brightest" people who are in large companies or slow-moving industries. They're ofte…

If they're really the best, wouldn't they have their pick of workplaces and optimize for personal enjoyment? Nobody who could chew through research level algorithm problems all day would willingly write Java 8 CRUD apps for Windows Server 2000, because those are the people that have a choice.

Re: IT Runs on Java 8

#396

Post by philwelch »

mzkply wrote: post #44

The HN front page is similar to any community. For example, a car site's homepage will be listing the latest supercars, expensive turbos, rims, whatever... while most readers are driving a $30,000 Civic. The best & brightest in tech are working with the best tools on the biggest problems, and that's what gets talked about, regardless of what the mass is doing.

> The best & brightest in tech are working with the best tools on the biggest problems, and that's what gets talked about, regardless of what the mass is doing.

That doesn't have to mean new and shiny.

By way of analogy: the F-117 stealth fighter--the world's first operational stealth aircraft--was developed by the best and brightest (Lockheed Martin Skunk Works) and solved the biggest problem (visibility to radar). Aside from having a weird polyhedral shape and innovative radar-absorbing material, nothing about the plane was the "best", "latest", or "cutting-edge" at all. Much of it consisted of parts from other aircraft hacked together. If you actually do want to have the best cutting-edge technology all in one plane, you spend 25 years designing the damn thing--that's the F-35.

Re: IT Runs on Java 8

#397

Post by mycall »

mzkply wrote: post #44

The HN front page is similar to any community. For example, a car site's homepage will be listing the latest supercars, expensive turbos, rims, whatever... while most readers are driving a $30,000 Civic. The best & brightest in tech are working with the best tools on the biggest problems, and that's what gets talked about, regardless of what the mass is doing.

I think mundane programmers could be some of the brightest, but for whatever reason, they don't go into the limelight to be noticed.

Re: IT Runs on Java 8

#398

Post by [deleted] »

overgard wrote: post #314
pron wrote: post #85

The funny thing is that from a purely technological point of view, Java (even the 5-year-old Java 8 and certainly recent versions) is far ahead of most other stuff hyped on HN (as well as less hyped stuff). Virtually no other platform comes close to that combination of state-of-the-art optimizing compilers, state-of-the-art GCs, and low-overhead in-production profiling/monitoring/management. And much of the cutting-e…

I used to be a Java hater (I'm much more neutral now -- I even find aspects of it pretty pleasant). To me, it was never about the technology of Java (always been pretty impressive), or even the language (a little verbose -- but so is C++ and C# and I like both of those), it was really just about the ecosystem. For whatever reason 2000s era java had soo many libraries that were just insanely over-engineered and had th…

[deleted]

Re: IT Runs on Java 8

#399

Post by sanderjd »

dragonwriter wrote: post #369
sanderjd wrote: post #313

Earlier quoted context omitted.

>> Most developers [from context: who want static types] turn to C++, Java, or C# > I'd be surprised if more than half (most) developers using static typing use those languages and not others outside that set. Really? I'd be surprised if it was less than 90%. What is the competition? Go, TypeScript, Swift, Scala, Kotlin, Rust (in rough order of my gut sense for how widely used they currently are)? These are all still…

> If you argue that C has static types, then I guess you're probably right. C (like C++) is both statically and weakly typed; strong and static typing are orthogonal axes (dynamic but strongly typed languages are common.) If you mean strong and static when you say static, you need to take C++ off your list.

Yeah, I kind of wondered about that as I was writing my comment, seems like a fair point.

Re: IT Runs on Java 8

#400

Post by mycall »

pron wrote: post #381
yawaramin wrote: post #358

Earlier quoted context omitted.

> Fibers are user-mode lightweight threads that allow synchronous (blocking) code to be efficiently scheduled, so that it performs as well as asynchronous code Sounds a lot like Erlang BEAM processes.

Yep; or Go's goroutines. Except that the fibers are implemented and scheduled in the Java libraries; the VM only provides continuations.

How does it compare to Windows fibers?
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