Clojure 1.10.1
user=> (def car 'ford)
#'user/car
user=> (def ford 3)
#'user/ford
user=> car
ford
user=> 'car
car
user=> (quote car)
car
user=> (eval (quote car))
ford
user=> (eval car)
3

user=> (load-file "Documents/cs378/cs378.clj")
#'user/kwote

user=> (def x (list 'a 'b 'c))
#'user/x
user=> x
(a b c)
user=> (empty? x)
false
user=> (cons? x)
true
user=> x
(a b c)
user=> (def y (cons 'd x))
#'user/y
user=> x
(a b c)
user=> y
(d a b c)

user=> (load-file "Documents/cs378/trace.clj")
#'user/deftrace

user=> (deftrace factorial [n]
	 (if (<= n 0)
	     1
	   (* n (factorial (- n 1))) ) )
#'user/factorial
user=> (factorial 5)
TRACE t251: (factorial 5)
TRACE t252: | (factorial 4)
TRACE t253: | | (factorial 3)
TRACE t254: | | | (factorial 2)
TRACE t255: | | | | (factorial 1)
TRACE t256: | | | | | (factorial 0)
TRACE t256: | | | | | => 1
TRACE t255: | | | | => 1
TRACE t254: | | | => 2
TRACE t253: | | => 6
TRACE t252: | => 24
TRACE t251: => 120
120
user=> (defn factorial [n]
	 (if (<= n 0)
	     1
	   (* n (factorial (- n 1))) ) )
#'user/factorial
user=> (factorial 10)
3628800

user=> (def saying '((a stitch in time) (saves nine)))
#'user/saying
user=> saying
((a stitch in time) (saves nine))
user=> (first saying)
(a stitch in time)
user=> (second saying)
(saves nine)
user=> (rest saying)
((saves nine))
user=> (second (second saying))
nine

user=> (def pattern '((- (- ?x ?y))    (- ?y ?x)) )
#'user/pattern
user=> pattern
((- (- ?x ?y)) (- ?y ?x))

user=> (deftrace length [lst]
	 (if (empty? lst)
	     0
	   (+ 1 (length (rest lst))) ) )
#'user/length
user=> (length '(a b c d))
TRACE t277: (length (a b c d))
TRACE t278: | (length (b c d))
TRACE t279: | | (length (c d))
TRACE t280: | | | (length (d))
TRACE t281: | | | | (length ())
TRACE t281: | | | | => 0
TRACE t280: | | | => 1
TRACE t279: | | => 2
TRACE t278: | => 3
TRACE t277: => 4
4
user=> (length '((a b) (c d)))
TRACE t284: (length ((a b) (c d)))
TRACE t285: | (length ((c d)))
TRACE t286: | | (length ())
TRACE t286: | | => 0
TRACE t285: | => 1
TRACE t284: => 2
2

user=> (defn sum [lst]
	 (if (empty? lst)
	     0
	   (+ (first lst) (sum (rest lst))) ) )
#'user/sum
user=> (sum '(1 3 27 4))
35

#'user/sumsq
user=> (defn sumsq [lst]
	 (if (empty? lst)
	     0
	   (+ (* (first lst) (first lst))(sumsq (rest lst))) ) )
#'user/sumsq
user=> (sumsq '(1 3 27 4))
755