There are a lot of interesting programming languages out there, but downloading and setting up the environment can be very time consuming when you just want to try one out. The good news is that you can try out many languages in your browser straight away, often with tutorials which guide you through the basics.
Following the pattern of 7 languages in 7 weeks book, here’s a somewhat abridged version.
Fed up of long compile times, want a lightweight environment for scripting? Dynamic languages could be your new friend.
Lua is a lightweight dynamic language with excellent coroutine support and a simple C API making it hugely popular in video gaming for scripting. Have fun with game engines like LÖVE and Marmalade Quick.
Clojure is the brainchild of the hugely charismatic speaker Rich Hickey, it is a descendant of one of the earliest programming languages LISP. There’s a really rich community around Clojure, one of my favourite projects is Sam Aaron’s Overtone live coding audio environment.
Try R (quick registration required)
R is a free environment for statistical computing and graphics, with a huge range of user-submitted packages. Ever wondered how to draw an egg?
Aspects of functional programming have permeated most mainstream languages from C++ to VB. However to really appreciate the expressiveness of the functional approach a functional-first language is required.
Erlang is a really interesting language for building fault tolerant concurrent systems. It also has great pattern matching capabilities. It has many industrial applications and tools including the RabbitMQ messaging system and the distribute database Riak.
Haskell is heavily based on the Miranda programming language which was taught in British universities in the 80s and 90s. Haskell added Monads and Type Classes, and is still taught in a few universities, it is also still quite popular in academic research.
OCaml like Miranda is based on the ML programming language adding object-oriented constructs. F# is based on OCaml, there is even a compatibility mode. OCaml still has industrial application, for example at Jane Street Capital and XenSource.
LiveScript is an indirect descendant of CoffeeScript with features to assist functional programming like pattern matching and function composition. Check out 10 LiveScript one liners to impress your friends.
Elm is a functional reactive language for creating highly interactive programs, including games. Reactive programming is an interesting direction and I think languages designed specifically for this are worth investigating.
Unfortunately there’s currently no online editor for this one, but there is a command line REPL. PogoScript is DSL friendly allowing white space in function names.
Esoteric languages tend to be write-only, a bit like Perl but just for fun.
With so many programming language experimentation environments available online, the next logical step is to host the IDE there. Imagine not having to wait 4 hours for Visual Studio to install.
Cloud 9 is an online environment for creating Node.js apps, pulling together sets of relevant packages. Tools like Sploder let you build games online.
The Try F# site offers arguably the most extensive online learning features of any language. Cloud Tsunami IDE also offers a rich online development experience for F#. In the near future CloudSharper will offer an online IDE experience for developing web applications with F# using WebSharper,
Once you’ve completed some basic tasks in a new language you’ll want to move on to slightly larger tasks. I like to use exercises from the coding Kata Catalogue like FizzBuzz, the Game of Life and Minesweeper.
Some people enjoy going through the Project Euler problems, others have their own hello world applications. For Martin Trojer it’s a Scheme interpreter and Luke Hoban often writes a Ray Tracer.
I’d also recommend joining a local meetup group. The London Scala meetup have a coding dojo every month and the F#unctional Londoners meetup have hands on session in the middle the month, the next one is on Machine Learning.
Programming language books that include questions at the end of sections are a good way to practice what you’ve learned but are few and far between. The recent Functional Programming with F# book is an excellent example of what can be done with questions at the end of each chapter.
While the basics of a language can be picked up in a few hours, expect it to take a few weeks before you’re productive and at least a few months before you start to gain mastery.
Want to write your own language? Pete Sestoft’s Programming Language Concepts book offers a good introduction to the subject.