;;3.10 Destructive functions
;Adam Nelson
;Chet Tobrey


(egs :3.10
     (eg '(setf x '(a b c))
         :of "assigning ( a b c ) to x"
         :out '(A B C))
     (eg '(setf y '(1 2 3))
         :of "assigning ( 1 2 3 ) to y"
         :out '(1 2 3))
     (eg '(append x y)
         :of "append is a pure function so x and y retain their values"
         :out '(A B C 1 2 3))
     (eg '(print x)
         :of " x retaining is original value"
         :out '(A B C))
     (eg '(print y)
         :of "y retains its original value"
         :out '(1 2 3))
     (eg '(nconc x y)
         :of "using nconc , a destructive function to combine the lists"
         :out '(A B C 1 2 3))
     (eg '(print x)
         :of "nconc has the side effect of altering its first argument"
         :out '(A B C 1 2 3))
     (eg '(print y)
         :of "y retains its initial value"
         :out '(1 2 3)))