std-adjoin | ![]() |
STD-ADJOIN
conses the element to the list if it doesn't not yet exist. It is used to extend a list without duplicate elements.
(std-adjoin 0 '(1 2)) => (0 1 2) (std-adjoin 1 '(1 2)) => (1 2) (std-adjoin 1 nil) => (1) (std-adjoin nil nil) => (nil)
x: any lisp expression.
lst: any proper list.
A list.
None.
(std-require 'STDLIST)
Defined in STDLIST