Getting started with the D Programming Language on OS X Yosemite

The D Programming Language is

a language with C-like syntax and static typing. It pragmatically combines efficiency, control, and modelling power, with safety and programmer productivity.

In this post, I’m going to quickly walk through getting a working D compiler setup on OS X Yosemite, using Homebrew.

I’m going to assume you’ve already got Homebrew installed and have a working installation. There are many guides on setting Homebrew up, so I’ll leave that to others.

Installing the D compiler, DMD

DMD is the standard D compiler, though there are others such as GDC (which targets GCC) and LDC (which targets LLVM). Usually it’s advised that you download the DMD package from the download page, but installation view Homebrew makes future upgrades far easier (and automates the installation process). To install DMD, run the following command:

brew install dmd

This may take a short while to complete, but once done you should have a working D compiler.

Testing the DMD compiler

Once you’ve got the DMD compiler installed, you’ll want to test it works. The easiest way is to create a file hello.d on your desktop with the following content:

import std.stdio;

void main()
{
    writeln("Hello world!");
}

Now to compile the file:

dmd ~/Desktop/hello.d

This shouldn’t throw any errors, but if it does then something is either wrong with your install or the source code you put in the file. If all went well, you should have an executable hello on your desktop. Run it as follows to see the output Hello world!.

~/Desktop/hello

Installing DUB - the D package manager

DUB is a package manager for the D Programming language, which makes managing dependencies for your programs super easy. If you’re writing any amount of D code, DUB will likely be very useful.

Luckily, installation is a breeze using Homebrew:

brew install dub

Creating a new project

DUB’s command line tool can help you to bootstrap new projects with a simple command. This is extremely useful as it scaffolds all of the required filesystem structure and creates the DUB package description file (dub.json). To create a new package called foo, run the following:

dub init foo

This will create a directory foo, with the following content:

foo
└── dub.json
└── source
    └── app.d

The dub.json should contain the following as standard:

{
    "name": "foo",
    "description": "A minimal D application.",
    "copyright": "Copyright © 2015, euan",
    "authors": ["euan"],
    "dependencies": {
    }
}

There are many more entries you can add to this package specification, all of which are detail in the package file format specification.

Compiling DUB based projects

DUB can be used to build packages. To do so, simply run dub build (or just dub) from within a package directory. This will create a single statically linked binary that you can run and/or distribute easily.