A little thought experiment has been running around in my head for the past couple of days. I thought I'd share it with you.
It's very hard to rank programming languages. We get a sense that some are good & some are bad, but the more experience you have the more caveats you have to allow: X is good (but it's hard to find good X programmers); Y is fairly bad (but it's good for data-wrangling), etc. Choosing the right language for the job is an art. But, as a novel way of looking at the problem, here's my thought experiment:
There's a 5-year project coming up. You don't know what it is. You don't know how many programmers will be working on it, or how good they'll be. You know nothing, except that it must be fairly large because it's a 5-year project.
You have one choice, and one objective. You get to choose the programming language for the project. And your objective is to guarantee that at the end of five years, the code-base is a sprawling, hideous, unmaintainable nightmare.
Which language do you pick?
You're not allowed to cheat. You have to pick a language you'd use for a real project. You can't choose assembly language, and you certainly can't choose Brainfuck.
I think this is an interesting way of thinking about the question for two reasons. First, whilst we spend so much of our time as programmers maintaining code, we spend surprisingly little time talking about maintenance. Or thinking about it. And second, the question isn't, "Which is the least maintainable language?", but rather, "Which languages tends to encourage the least maintainable behaviour?"
I think I've made my choice. I think I'm picking Perl.
Now don't get me wrong, I like Perl a lot. I seem to like Perl more than most people I meet. It's particularly strong at text-handling, and makes a good choice when you're forced to resort to screen-scraping semi-structured data.
But Perl does not lend itself well to large, clear code bases. It has a good object model, but it doesn't enforce it. It doesn't even really recommend it. It's just there in case anyone's interested.
It has something like a recommended project structure, but unless you're producing modules for CPAN or you've stumbled upon the object model, you'll probably miss it.
And worst of all there's very little unity of approach. Ask five Java programmers to write a simple program, and by-and-large all five of them will come up with a similar answer. Ask five Perl programmers, and they'll all have a different preferred approach. And they'll probably all take pride in how novel their solution is. That's all good fun, but having five ways to do the same simple thing doesn't lend itself to large scale coding.
I could pick other languages. The worst coding crimes I've ever seen have all been in PHP. But for an absolute lack of unity, I'm picking Perl.
What would you pick?