On Fibonacci Haskell

In response to Dan Weber blog entry about Fibonacci in Haskell, I thought I should provide this link about The Evolution of a Haskell Programmer which covers in depth the proper implementation of Fibonacci in Haskell ;)

Partition and Solve

The idea of breaking programs into functions was taught to some of us with the metaphor of "divide and conquer." That is, make several smaller problems and solve those instead.
This approach is now so deeply ingrained that I can just think "partition and solve" which is of course a much more positive and accurate description.
One might think of the "partition your program into functions" principal as "the divide and conquer" principal. But of course, they are both instance of the more general "partition and solve". I dare say that "partition your program into functions" is even a more pure and accurate instance of the principal.
Evolution may also be an instance of the principal. Different species evolved to solve different problems, or to solve the same problem (survival) in different ways.
Of course, when you partition a program into functions, you also define those functions' relationships to each-other. Just because you're partitioning doesn't mean that the problems are not related.
When people see several competing projects in the "free software community" trying to solve the same problem, some might say, "Good. We have divided them, now we will conquer them!" In their marketing material (or more likely press-release ranting) they will say that a house divided against itself will not stand [1].
Such people are probably purposefully ignoring the "partition and solve" principal. They ignore the fact that different projects have chosen different paths to solve different problems. They ignore the relationships between the projects, and that we feed each-other much more often than we actually compete. But no good programmer will ignore the relationships between her functions.
Even within the Debian project we have lots of different goals. A truly gifted project leader will hopefully not see Debian as a house divided, but rather a very ripe partitioning looking for someone to define the problem that we solve together. A leader should help to define, create, or encourage the relationships that make that solution happen.
peace,

isaac

[1] Oh no, I've contradicted the Bible and praised evolution in the same essay! Well, not really. The fallacy is not with the Bible's assertion about the house divided against itself, it's in the interpretation of "the free software community" as a single house. And also, I believe God created evolution :)