item—an object.
sequence—a proper sequence.
predicate—a designator for a function of one argument that returns a generalized boolean.
from-end—a generalized boolean. The default is false.
test—a designator for a function of two arguments that returns a generalized boolean.
test-not—a designator for a function of two arguments that returns a generalized boolean.
start, end—bounding index designators of sequence.
The defaults for start and end are 0
and nil
, respectively.
key—a designator for a function of one argument,
or nil
.
element—an element of the sequence, or nil
.
find
, find-if
, and find-if-not
each search for an element of the sequence
bounded by start and end
that satisfies the predicate predicate
or that satisfies the test test or test-not,
as appropriate.
If from-end is true, then the result is the rightmost element that satisfies the test.
If the sequence contains an element that satisfies the test,
then the leftmost or rightmost sequence element,
depending on from-end,
is returned;
otherwise nil
is returned.
(find #\d "here are some letters that can be looked at" :test #'char>) → #\Space (find-if #'oddp '(1 2 3 4 5) :end 3 :from-end t) → 3 (find-if-not #'complexp '#(3.5 2 #C(1.0 0.0) #C(0.0 1.0)) :start 2) → NIL
Should be prepared to signal an error of type type-error
if
sequence is not a proper sequence.
position, Section 17.2 (Rules about Test Functions), Section 3.6 (Traversal Rules and Side Effects)
The :test-not argument is deprecated.
The function find-if-not
is deprecated.