D, or What Go May Have Been

In my quest to learn more and more programming languages, I recently dipped my toes into the D Programming Language. My reaction to it involves sadness; on the positive side of things, the language is undeniably brilliant.

On the other side, it is an almost completely ignored language, at least in the circles I use to move. In my 25 years of professional experience, I only met one developer using D for work; the language hardly (if ever) shows up in technical discussions. The official website says that D is used by eBay, Netflix, Facebook, and others, so thankfully it has found certain niches where it shines.

But D deserved more.

As usual, I implemented my Conway and Fortune projects with it. The development experience is brilliant, on par with Go (hence the title of this blog,) C#, TypeScript, and other modern languages. The compiler generates fast code fast, the language has lots of modern features, and in general, it qualifies as a boring language. Again, in my own scale of values this is a positive trait of a programming language.

Developers coming from C++, C#, Java, and Go will find D immediately approachable.

import std;
import core.thread;
import conwaylib;

void clrscr()

void main()
    Coord[] alive = blinker(Coord(0, 1));
    alive ~= blinker(Coord(0, 1));
    alive ~= beacon(Coord(10, 10));
    alive ~= glider(Coord(4, 5));
    alive ~= block(Coord(1, 10));
    alive ~= block(Coord(18, 3));
    alive ~= tub(Coord(6, 1));

    World world = World(30, alive);
    int generation = 0;
    while (true)
        writeln(format("Generation %d", generation));
        world = world.evolve();

In many ways, D is like Go. It uses garbage collection, has a nice library with everything you need out-of-the-box, is cross-platform (available for Windows, macOS, all major Linux distributions, Android, and even FreeBSD,) has functional programming features, has integrated unit testing, a package manager, and much more. It also adds some features that Go has not. For example, D integrates unit tests with documentation generation (a fantastic idea!) It also features class inheritance–because, after all, D was meant to replace C++.

Unfortunately, and quite obviously, D is not Go. I say unfortunately because such a language, with such an ecosystem around it, and with such luminaires at its helm (Walter Bright and Andrei Alexandrescu being just a few of them), deserved better. Better, for example, than not even being mentioned in the Stack Overflow 2021 survey of most popular technologies. This is, simply put, not fair; dura lex, sed lex.

And now Google, after Go, Dart, and how many more languages, is positioning yet another one, this time called Carbon, as a successor of C++. Such privilege belongs to D, not to Carbon. But market forces are something to be reckoned, and at this point it is not obvious how the D Language Foundation could curb them.

Politics and stock market value have a lot to say in the war for programming language supremacy. Go has had its “killer app” with Kubernetes, and as a result Go is 15th in the August 2022 TIOBE ranking, while D appeared 20 positions lower. Go is 11th in the IEEE Spectrum ranking, while D appears at the 27th position. Go is 9th in PYPL at the time of this writing, and 16th in the RedMonk ranking, and D doesn’t even appear in either list.

D is ready, powerful, easy to learn, compatible, cross-platform, fast, extensible, and fun. There’s a lot to like in there. But it lacked a “killer app.”