D

D is the fourth letter of the Latin alphabet, an unofficial symbol for ²H and a modern programming language, billed (by some at least!) as the successor to C++.

Installing the D compiler

Add the D apt respository in /etc/apt/sources.list.d/dlang.list:

deb http://netcologne.dl.sourceforge.net/project/d-apt/ d-apt main

Then get the apt key:

apt-get update && apt-get -y --allow-unauthenticated install --reinstall d-apt-keyring

Then install the things:

apt-get install dmd-bin dcd dub

Optionally grab a D-aware IDE, and go check out all the packages available in the DUB repository.