Question

I was recently looking for a personal wiki and come upon Hatta, which uses Markdown simplify to editing and generate html. My question is why are there some many implementations of Markdown in Python, Javascript, PHP, etc. when an official Perl implementation already exists? Is there some benefit to having this choice?

Answer 1

One point is that it’s easier to rewrite than attempt to integrate a Perl script with whatever other language happens to be in use for development.

Another point is that John Gruber hasn’t updated the original implementation in over five years, and quite a few people want something or other that isn’t present in the original, so they add it themselves, often re-implementing it in the process.

Another point is that no matter how hard people push reuse of software, quite a few people have at least a little NIH attitude hidden somewhere, so they re-implement things unnecessarily. That’s not entirely bad either — it can help understanding, as well as lead to cleaner implementations over time (I have to say that — I’m more guilty than most of writing my own instead of reusing what’s already available).

People often start by writing something mostly for understanding — but in the case of markdown, the specification is sufficiently simple that it’s often hard to tell the difference between something written as an exercise for the author’s own use, and code that’s really suitable for production (a lot of web developers also lack the experience to know the difference, at least very well).