>>12`@` was always a part of LISP
https://stackoverflow.com/questions/21463925/meaning-of-at-sign-in-lisp[bare words list] is a classic POP11 syntax for lists, and is frequently introduced into LIPS dialects
`_` is a also classic symbol from LISPs with pattern matching:
https://blog.theincredibleholk.org/blog/2013/02/11/matching-patterns-with-scheme/In pattern matchers `@` becomes a kleene star, which also binds the value. If `@` has no name, it is assumed to be @_
`~` is autoextractor, saves from typing and thinking about temporary variables names.
`$` servers a role of backtick, cuz I use `back ticks` for symbols, instead of the classic |symbol name|. Instead `|` is being used of a more useful thing.
`{}` - map operator. In the simplest form `Xs{X=Y}` acts as the usual LISP map, but due to pattern matching nature, it can also do stuff like `Pixels{R G B = B G R}` to swap color order, or [0:9]{?%2=} to strip odd integers
`(A=B;C=D,...,N=M)` is a transliteration operator
`(:...)` advanced form of the above, which has builtin y-combinator shortcut for quickly processing trees.
So Xs(~@) would be (car Xs) in usual LISP, Xs(_@~) would be (cdr Xs). But default these return `No` on failure but I can changer it into error Xs(bad 'pattern match failed':_@~), or return an empty list Xs([]:_@~). That saves immense amount of typing and screen space, because 50% of LISP code deals with lists that could have no car or no tail.
In fact, Symta doesn't have CAR and CDR, instead it has OOP subsystem, and lists expose head and tail methods. That way users can define their own list types, which will work with the pattern matcher machinery. For example, hash tables can be converted to lists of key-value pairs.