Deprecated: The each() function is deprecated. This message will be suppressed on further calls in /home/zhenxiangba/zhenxiangba.com/public_html/phproxy-improved-master/index.php on line 456

is_cons : term -> bool

SYNOPSIS: Tests a term to see if it is an application of CONS.
DESCRIPTION: is_cons returns true of a term representing a non-empty list. Otherwise it returns false.
FAILURE CONDITIONS: Never fails.
SEE ALSO: dest_cons, dest_list, is_list, mk_cons, mk_list.