Lisp and data structures: one reason it hasn't attracted me
I've written before about some small scale issues with reading languages that use Lisp style syntax, but I don't think I've said what I did the other day on Twitter, which is that the syntax of how Lisp languages are written is probably the primary reason that I slide right off any real interest in them. I like the ideas and concepts of Lisp style languages, the features certainly sound neat, and I often use all of these in other languages when I can, but actual Lisp syntax languages have been a big 'nope' for a long time.
(I once wrote some moderately complex Emacs Lisp modules, so I'm not coming from a position of complete ignorance on Lisp. Although my ELisp code didn't exactly make use of advanced Lisp features.)
I don't know exactly why I really don't like Lisp syntax and find it such a turn-off, but I had an insight on Twitter. One of the things about the syntax of S-expressions is that they very clearly are a data structure. Specifically, they are a list. In effect this gives lists (yes, I know, they're really cons cells) a privileged position in the language. Lisp is lists; you cannot have S-expressions without them. Other languages are more neutral on what they consider to be fundamental data structures; there is very little in the syntax of, say, C that privileges any particular data structure over another.
(Languages like Pyhton privilege a few data structures by giving them explicit syntax for initializers, but that's about it. The rest is in the language environment, which is subject to change.)
Lisp is very clearly in love with lists. If it's terribly in love with lists, it doesn't feel as if it can be fully in love with other data structures; whether or not it's actually true, it feels like other data structures are going to be second class citizens. And this matters to how I feel about the language, because lists are often not the data structure I want to use. Even being second class in just syntax matters, because syntactic sugar matters.
(In case it's not clear, I do somewhat regret that Lisp and I have never clicked. Many very smart people love Lisp a lot and so it's clear that there are very good things there.)