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count-if-not 122
sequence can be either a list or a vector (one-dimensional array). Note that
nil is considered to be a sequence, of length zero.
The value of the keyword argument : key, if non-nil, is a function that
takes one argument. This function extracts from each element the part to
be tested in place of the whole element.
For example:
(count-if #'atom '«a b) «a) b) (nil nil» :key #'car) => 2
I
(count-if #'zerop #(1 2 1) :key #'(lambda (x) (- x 1») => 2
The :from-end argument does not affect the result returned; it is accepted
purely for compatibility with other sequence functions.
For example:
(count-if #'oddp '(1 1 2 2) :start 2 :from-end t) => B
(count-if #'oddp '(1 1 2 2) :start 2 :from-end nil) => B
For the sake of efficiency, you can delimit the portion of the sequence to be
operated on by the keyword arguments :start and :end.
:start and :end must be non-negative integer indices into the sequence.
:start must be less than or equal to : end, else an error is signalled. It
defaults to zero (the start of the sequence).
:start indicates the start position for the operation within the sequence.
:end indicates the position of the first element in the sequence beyond the
end of the operation. It defaults to nil (the length of the sequence).
If both :start and :end are omitted, the entire sequence is processed by
default.
For example:
(count-if #'oddp '(1 2 1 2» => 2
(count-if #'oddp '(1 1 1 222) :start 2 :end 4) =>
(count-if #'numberp , (heron 1.B a 2 #\Space» => 2
For a table of related items: See the section "Searching for Sequence
Items" in Symbolics Common Lisp: Language Concepts.
count-if-not predicate sequence &key key from-end (start 0) end Function
count-if-not returns a non-negative integer, which represents the number
of elements in the specified subsequence of sequence that do not satisfy the
predicate.