Intro to Haskell, Parts 1, 2 and 3

It's been a while since I've posted here (too long, in fact!).

Readers of this blog would probably be interested in a set of three articles I'm writing for the O'Reilly Network. The first two are available now:

• Part 1: Why Haskell?
• Part 2: Pure Functions

My goals here are to reach the core audience for ONLamp: Perl, Python, PHP and Ruby programmers. Haskell is a very big step away from dynamic languages, and it's also a big change from statically typed languages in the ALGOL family (C, and its descendants C++, Java and C#). The first article makes the case that, although Haskell is strange and different, it's worth the effort to learn -- even if you never manage to use it on a job or a side project. The second article shows how it is possible to write programs using pure functions in the absence of all the familiar tools -- classes, objects, globals and mutable variables.

I'm working on part 3, which will be an introduction to monads. This is something of a rite of passage, because writing monad intros is something of a cottage industry in the Haskell world -- either you've written one, or you're still a dabbler, beginner, or casually interested in Haskell (and not committed to delving into it).

Articles on ONLamp should be article length, oddly enough. That means roughly 2000 words or so. Given that tutorials like All About Monads run dozens of pages, condensing a full tutorial into a single article is hopeless.

Rather than attempt to outdo what many other fine tutorials are going very well already, I'm taking a different approach. The one thing I want to focus on is the mechanics of monads. That is, how they work. Maybe that will be the missing link that the next wave of programmers need to see before they can study Haskell.

Part 3 should be published in a couple of weeks.