[Haskell-cafe] Why functional programming matters

[Yaakov Nemoy]

On Jan 23, 2008 8:29 AM, Simon Peyton-Jones <simonpj at microsoft.com> wrote:
> Friends
>
> Over the next few months I'm giving two or three talks to groups of *non* functional programmers about why functional programming is interesting and important.  If you like, it's the same general goal as John Hughes's famous paper "Why functional programming matters".
>
> Audience: some are technical managers, some are professional programmers; but my base assumption is that none already know anything much about functional programming.
>
> Now, I can easily rant on about the glories of functional programming, but I'm a biased witness -- I've been doing this stuff too long.  So this message is ask your help, especially if you are someone who has a somewhat-recent recollection of realising "wow, this fp stuff is so cool/useful/powerful/etc".
>
> I'm going to say some general things, of course, about purity and effects, modularity, types, testing, reasoning, parallelism and so on. But I hate general waffle, so I want to give concrete evidence, and that is what I particularly want your help with.  I'm thinking of two sorts of "evidence":

I'm still very much a newbie, but the one thing that struck me as the
best feature coming from Python is the static typing.  Changing the
type of a function in Python will lead to strange runtime errors that
take some work to debug, whereas, when I tinker with a program in
Haskell, I already know it will work once it compiles.

-Yaakov