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10.2.2 List predicates

Function: proper-list? x
[SRFI-1] Returns #t if x is a proper list.

Function: circular-list? x
[SRFI-1] Returns #t if x is a circular list.

Function: dotted-list? x
[SRFI-1] Returns #t if x is a finite, non-nil-terminated list. This includes non-pair, non-() values (e.g. symbols, numbers), which are considered to be dotted lists of length 0.

Function: null-list? list
[SRFI-1] Returns #t if list is the empty list (), and #f if list is a non-null, proper or circular list. This procedure signals an error if list is not a proper or circular list.

Function: not-pair? x
[SRFI-1] (lambda (x) (not (pair? x))).

SRFI-1 says: Provided as a procedure as it can be useful as the termination condition for list-processing procedures that wish to handle all finite lists, both proper and dotted.

Function: list= elt= list ...
[SRFI-1] Determines list equality by comparing every n-th element of given lists by the procedure elt=.

It is an error to apply list= to anything except proper lists.

The equality procedure must be consistent with eq?, i.e.
 
(eq? x y) => (elt= x y).



This document was generated by Ken Dickey on November, 28 2002 using texi2html