When I see such cool projects, I feel very overwhelmed. How do you get started with Rust and master basics to even attempt doing such a thing? Can OP explain?
I have written a JVM in Rust
81–90 of 185 posts
Re: I have written a JVM in Rust
#82Earlier quoted context omitted.
Seems… redundant, no?
Nope. For a more realistic example of such a JVM, look at SubstrateVM (written in "SystemJava" and compiled to native code ahead of time along with the app it runs), and "Java on Truffle" (a.k.a. Espresso), which is a JVM written in Java designed to be compiled to run on top of SubstrateVM. Both projects are a part of Graal. The reason to do this, beyond the inherently neat Inception factor, is that JVMs are a PITA t…
I find that Rust is like maybe 1.5-2x more productive to code in than say C or C++. Part of that is the tooling has so much less arcane baggage, part of that is that I need to reach less for external tools for metaprogramming, part of that is fewer crazy macro/template compiler errors, and part of that is less time spent debugging.
It all adds up.
Re: I have written a JVM in Rust
#83That is pretty awesome! When I joined the Java effort in '92 (called Oak at the time) the group I was with was looking at writing a full OS in Java. The idea being that you could get to just the minimal set of things needed as "machine code" (aka native methods) you could reduce the attack surface of an embedded OS. (originally Java was targeted to run in things like TV's and other appliances). We were, of course, wo…
There was one for a while though wasn't really targeted at users:
Re: I have written a JVM in Rust
#84When I see such cool projects, I feel very overwhelmed. How do you get started with Rust and master basics to even attempt doing such a thing? Can OP explain?
Likewise. Not to go onto too much of tangent, but on a more personal note I've been generally struggling with this feeling a lot lately.
I've been a professional software developer for almost 10 years, and I _know_ I'm competent (and not an impostor) as demonstrated by my current position and ability to ship things.
However, lately after viewing developer blogs I become overwhelmed that I actually don't know enough and am not a "real" developer. I seem to have formed a notion of an ideal developer in my head and I compare myself against this imagined construct which leads to these feelings. I admire how these people have so much deep knowledge and can express themselves so clearly and concisely, then wonder why I am not like that.
I barely have the energy after work after taking care of my family to do anything further, and I know programming isn't everything but I do have a desire to learn more and improve myself.
I recognize this isn't healthy nor is it rational, but it's just a feeling I can't shake lately.
Re: I have written a JVM in Rust
#85When I see such cool projects, I feel very overwhelmed. How do you get started with Rust and master basics to even attempt doing such a thing? Can OP explain?
Not OP nor am I a Rust expert. I can speak regarding another technology: sockets.
I've been deep-diving into sockets recently. 2 weeks ago I had only a high-level understanding of sockets (learned from casually reading manpages, docs, blog posts, etc.). I decided to read as much as possible because I wanted to understand networking fundamentals, and after a week I learned enough to write some sockets code in Python and C. I know Python quite well, so reviewing the ``sockets'' library made more sense after my deep dive.
If you want to get better at technology A using language X, I suggest either reading/watching as much as you can about tech A, and build stuff with it in language Y. Then you can circle back to learning language X and you've already mastered much of the concepts around technology A.
e: spelling
Re: I have written a JVM in Rust
#86Earlier quoted context omitted.
Thanks, makes sense yes. Still if the JVM look up in all cases defers to value after ref mismatch, it should work identically, no? Even if interning is mandatory as per spec, I'm not sure how it'd change the outcome of evaluation.
The problem is that, per the spec, the following must hold: if("abc" == "abc") { System.out.println("correct"); } if(new String("abc") != new String("abc")) { System.out.println("correct"); } So, not having proper string interning support means that you mis-execute certain programs.
Sure, but also consider that this JVM (intentionally) lacks support for other things that all but the most trivial programs would use. I don't think it's expected by the author that you can throw any random program at it. It's really there just to run your own programs that you've written specifically for it in order to play around with things. And since you know you're writing for this particular JVM, you should know not to do anything that depends on string interning, among other things.
Re: I have written a JVM in Rust
#87That is pretty awesome! When I joined the Java effort in '92 (called Oak at the time) the group I was with was looking at writing a full OS in Java. The idea being that you could get to just the minimal set of things needed as "machine code" (aka native methods) you could reduce the attack surface of an embedded OS. (originally Java was targeted to run in things like TV's and other appliances). We were, of course, wo…
Besides the sibling comments,
- SavageJE
- microEJ
- PTC and Aonix bare metal Java runtimes
- SunSPOT mit SquawkVM
Re: I have written a JVM in Rust
#88When I see such cool projects, I feel very overwhelmed. How do you get started with Rust and master basics to even attempt doing such a thing? Can OP explain?
Break things down. A simple language VM is going to have a way to represent objects in memory, a byte code interpreter, a simple garbage collector, and a way to load things.
A byte code interpret is a stack, some way to represent functions on that stack, and then a loop to interpret beach byte code and move the program counter.
Re: I have written a JVM in Rust
#89Earlier quoted context omitted.
Seems… redundant, no?
Nope. For a more realistic example of such a JVM, look at SubstrateVM (written in "SystemJava" and compiled to native code ahead of time along with the app it runs), and "Java on Truffle" (a.k.a. Espresso), which is a JVM written in Java designed to be compiled to run on top of SubstrateVM. Both projects are a part of Graal. The reason to do this, beyond the inherently neat Inception factor, is that JVMs are a PITA t…
And Jikes RVM as well.
Re: I have written a JVM in Rust
#90When I see such cool projects, I feel very overwhelmed. How do you get started with Rust and master basics to even attempt doing such a thing? Can OP explain?
Well, _I_ feel impostor syndrome half the times I open HN honestly!
I did have a bit of experience with VMs before, I wrote many years ago a short series of posts about it on my blog, and at my previous job I dabbled a bit in JVM byte code to solve one very unusual problem we had for a customer. I also read the _amazing_ https://craftinginterpreters.com/ years ago and that gave me some ideas.
But this project was definitely big and complex. It took me a lot of time, and it got abandoned a couple of times, like many of my side projects. But I'm happy I finished it. :-)