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An association list is a list representing a mapping from one set of values to another; any list whose elements are cons cells is an association list.
This function searches the association list a-list for an element whose car matches (in the sense of
:test
,:test-not
, and:key
, or by comparison witheql
) a given item. It returns the matching element, if any, otherwisenil
. It ignores elements of a-list that are not cons cells. (This corresponds to the behavior ofassq
andassoc
in Emacs Lisp; Common Lisp'sassoc
ignoresnil
s but considers any other non-cons elements of a-list to be an error.)
This function searches for an element whose cdr matches item. If a-list represents a mapping, this applies the inverse of the mapping to item.
The cl-assoc-if
, cl-assoc-if-not
, cl-rassoc-if
,
and cl-rassoc-if-not
functions are defined similarly.
Two simple functions for constructing association lists are: