Re:An Intuition for Lisp Syntax
by EE84M3i on Monday October 26, 2020 @12:08AM
(#24892752)
IMO, by far the most confusing thing about lisp syntax is not code data duality, but instead that when you actually dive into the specs for these languages, its actually still really complicated and full of edge cases. A "toy" lisp can be simple sure, but "real" lisps aren't.
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The formal Scheme syntax spec is, what?, a few pages. Far smaller than any other "real" language I'm aware.
I'm not too familiar with scheme, but syntax seems to be at least a few dozen pages here? www.r6rs.org/final/r6rs.pdf
Also compare https://people.csail.mit.edu/jaffer/r5rs_9.html and e.g. https://docs.python.org/3/reference/grammar.html which I would consider a relatively syntactically rich language.
R6RS was the largest Scheme spec ever, and because of it the next one was actually reduced into two: R7RS-small (core-language) and R7RS-big (extended).
The R7RS-small standard [0] has already been ratified. It is a similar size to R6RS as a document size, but the semantics are about 8 pages, and include a bunch of macros that you don't need to implement, but just copy and paste into your implementation.
I'd say it's a similar sized grammar to Python's.
What I see is that the Scheme one is a lot more thorough and still shorter.
Real schemes are much more complicated. I think he’s talking about Common Lisp though.
I enjoy lisp/scheme syntax, but I'm especially impressed by lua's simple, readable, flexible, whitespace-insensitive-but-whitespace-friendly syntax. It is a bit more complicated than scheme's, but more intuitive because you don't need to explain quasi-quoting and other lisp-specific stuff.
https://www.lua.org/manual/5.4/manual.html#9