The last few months I’ve been using Emacs extensively as my main development environment and I’ve now come to a point at which I’d like to learn it’s own Emacs Lisp to write my own little stuff for Emacs and extend it to my personal needs.
Having said that I’ve also wanted to learn Common Lisp for a while now, to play around with and explore a new language. My question is, where should I start from? Will Emacs Lisp give me the necessary knowledge to pick up Common Lisp later more easily or the other way round? I’m basically interested in the efficiency of each path so as to minimize the learning curve when I finally decide to move from one dialect to the other.
Start with Emacs Lisp (given that you seem to have already started customizing your emacs) – it seems to be more immediately useful for you.
Do keep in mind that there is quite a bit of difference between Emacs Lisp (there is a lot of buffer management stuff, especially in the code you’re likely to see in the wild) and Common Lisp (more similar to a general purpose programming language), so which ever route you take, expect some amount of “wastage”