'foo ; the symbol FOO (the reader upcases)
'|Mixed Case| ; |Mixed Case|: vertical bars preserve case and spaces
(symbol-name 'foo) ; "FOO"
(intern "BAR") ; BAR, NIL/:INTERNAL (find or create a symbol in the current package)
(find-symbol "CAR" :cl) ; CAR, :EXTERNAL
(make-symbol "TEMP") ; #:TEMP: an uninterned symbol
(gensym "TMP") ; #:TMP123: a fresh uninterned symbol (used in macros)
(symbol-package 'car) ; #<PACKAGE "COMMON-LISP">
(symbolp 'a) (keywordp :a) ; T T
;; A symbol has: a name, a package, a value cell, a function cell, and a property list
(setf (symbol-value 'my-var) 42) ; global value (like defparameter without declaring special)
(boundp 'my-var) ; T
(symbol-value 'my-var) ; 42
(fboundp 'car) ; T
(symbol-function 'car) ; #<FUNCTION CAR>
(symbol-plist 'apple) ; the property list
;; Keywords live in the KEYWORD package and evaluate to themselves
:name ; :NAME
(eq :name
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