Some forms of nonatomic S-expressions arise so frequently there is a special notation for them. A dotted-pair of the form ( S 1 . ( S 2 . (· · · . ( S k . NIL)· · ·))) where S 1, S 2, . . . , S k are all S-expressions is called a list and is written as ( S 1 S 2 ... S k ), which is the sequence of S-expressions S 1, S 2, . . . , S k written with intervening blanks and enclosed in parentheses. There is no confusion with dot notation since there are no dots between the S i elements in the list. There may, of course, be dots within some or all of the elements S 1, . . . , S
© Gary D. Knott 2017
Gary D. Knott, Interpreting LISP, 10.1007/978-1-4842-2707-7_10
10. List Notation
Gary D. Knott1
(1)Civilized Software Inc., Silver Spring, Maryland, USA
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