Ask HN: Why do you use Rust, when D is available?

#1

Post by crazypython » Thu, Jun 11, 2020, 11:56 PM UTC

D supports Ownership and Borrowing, just like Rust. DMD, D's reference compiler, can compile itself in less than 5 seconds, thanks to a fast frontend and fast backend. D is easy to metaprogram through traits and templates. You can make your own JIT in D with dynamicCompile.

I'd love to hear some reasons why so D and Rust can learn from each other.

Re: Ask HN: Why do you use Rust, when D is available?

#2

Post by narrationbox » Fri, Jun 12, 2020, 12:56 AM UTC

First mover. For a long time D targeted the same abstraction level as Go, and most of its libraries were designed with that in mind. Stuff like no_std was never a major goal for most supposed "systems languages" (that are not C/C++) until Rust came along. D was too slow in gaining momentum, getting corporate sponsorship, and adding new features that pushed the boundaries of what a systems programming language was capable of. Go had first class tooling, D felt like a C++ with a Garbage Collector. It reminds me a lot of Ocaml which also had a lot of great ideas and occasionally showed up in the engineering blog of a major corporation but if you look closely then you would notice severe issues with package management and multithreading (both of which are finally getting attention and being fixed, 5 years too late). There are a lot of boring engineering that goes into making a good programming language ecosystem that many smaller languages do not have either the willpower or resources in tackling.

This is not criticism of the D language, programming languages are like startups, success often has little to do with the product itself but more the ecosystem, funding, and luck.

Re: Ask HN: Why do you use Rust, when D is available?

#3

Post by Buttons840 » Fri, Jun 12, 2020, 1:22 AM UTC

It seems to me that D has been too many places and has too many features. My impression is that D sometimes uses a GC, sometimes not. I believe I can do many interesting things in D once I learn the language well enough to pick a certain subset of features, much like C++. In other words, if I want to write GC free code in D I have to learn what NOT to use.

If I want to pick a subset of features, I'd probably pick C++. Or, if I'm willing to use a GC and runtime, then there's lots of languages to choose from.

I use Rust if I want "safety" and no GC and that's all I get.

This is my impression. But I know very little of D so do not judge the language based on my impressions.

Re: Ask HN: Why do you use Rust, when D is available?

#4

Post by thomastjeffery » Fri, Jun 12, 2020, 1:25 AM UTC

The syntax is nicer.

Granted, I'm not very familiar with D. I didn't even know it had a borrow checker.

Rust took a lot of great features from Haskell, while keeping itself reasonably approachable from a C/C++/D/Java programmer's perspective.

Rust put type names after variable/function/parameter names, which really cleans up the syntax nicely.

Rust has very nice syntax for pattern matching, monads, and a slew of other really helpful functional language features.

Even if rust didn't have a borrow checker, it would still be a wonderful systems programming language.

Re: Ask HN: Why do you use Rust, when D is available?

#5

Post by gaze » Fri, Jun 12, 2020, 2:08 AM UTC

I can't tell if D is supposed to be used with or without the GC. I just know Rust is pretty close to an ML, which I like, and it has this nice borrow checker and is super popular.

Re: Ask HN: Why do you use Rust, when D is available?

#6

Post by juststeve » Fri, Jun 12, 2020, 2:41 AM UTC

thomastjeffery wrote: post #4

The syntax is nicer. Granted, I'm not very familiar with D. I didn't even know it had a borrow checker. Rust took a lot of great features from Haskell, while keeping itself reasonably approachable from a C/C++/D/Java programmer's perspective. Rust put type names after variable/function/parameter names, which really cleans up the syntax nicely. Rust has very nice syntax for pattern matching, monads, and a slew of othe…

Also option / result types as well which are super nice

Re: Ask HN: Why do you use Rust, when D is available?

#7

Post by viraptor » Fri, Jun 12, 2020, 2:47 AM UTC

From what I understand D ownership is based on function attributes which means it's enforced only across function calls and only as an opt-in. In Rust this is done across everything, so function basic blocks are also validated.

Re: Ask HN: Why do you use Rust, when D is available?

#8

Post by sesuximo » Fri, Jun 12, 2020, 2:49 AM UTC

I love D but I think the GC is a good argument for Rust

Re: Ask HN: Why do you use Rust, when D is available?

#9

Post by jdxcode » Fri, Jun 12, 2020, 2:52 AM UTC

Engineers learn languages because of success stories by other companies—not by the merits of the syntax or one-off tricks like compiling itself in 5 seconds.

The fact that Firefox uses Rust for the browser engine or that Dropbox uses Rust for the sync engine is the kind of thing that gets me interested.

Re: Ask HN: Why do you use Rust, when D is available?

#10

Post by alexashka » Fri, Jun 12, 2020, 2:52 AM UTC

Because Rust is new and shiny.

People who use Rust aren't using it to solve real world problems, they're using it to scratch a novelty itch.

D is a tragedy in my opinion. It's an excellent language that just doesn't fit the political needs of any of the big players.

We have Swift which is a worse version of C#, we have Go, we have Java. Why don't we have a single language so that we can do cross platform development and abandon web browsers and javascript? Because politics. Every company needs to toot its own horn and suck up smart intelligent people so that they don't create a real competitor, and so we have a dozen languages that share 95% of the features and are all incompatible with one another and no one sane enough to say this is crazy, I'm going to take my FAANG money, move to a place with cheap rent and put an end to this madness.

It's only a game developer of all people, Jonathan Blow, that's doing it and his creation is a C++ replacement for games, not general purpose software. Sigh.