mismatch sequence-1 sequence-2
&key from-end test test-not key start1 start2 end1 end2
⇒ position
| Sequence-1 | a sequence. |
| Sequence-2 | a sequence. |
| 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. |
| start1, end1 | bounding index designators of sequence-1.
The defaults for start1 and end1 are 0 and nil, respectively.
|
| start2, end2 | bounding index designators of sequence-2.
The defaults for start2 and end2 are 0 and nil, respectively.
|
| key | a designator for a function of one argument, or nil. |
| position | a bounding index of sequence-1, or nil. |
The specified subsequences of sequence-1 and sequence-2 are compared element-wise.
The key argument is used for both the sequence-1 and the sequence-2.
If sequence-1 and sequence-2 are of equal length and match in every element, the result is false. Otherwise, the result is a non-negative integer, the index within sequence-1 of the leftmost or rightmost position, depending on from-end, at which the two subsequences fail to match. If one subsequence is shorter than and a matching prefix of the other, the result is the index relative to sequence-1 beyond the last position tested.
If from-end is true, then one plus the index of the rightmost position in which the sequences differ is returned. In effect, the subsequences are aligned at their right-hand ends; then, the last elements are compared, the penultimate elements, and so on. The index returned is an index relative to sequence-1.
(mismatch "abcd" "ABCDE" :test #'char-equal) ⇒ 4
(mismatch '(3 2 1 1 2 3) '(1 2 3) :from-end t) ⇒ 3
(mismatch '(1 2 3) '(2 3 4) :test-not #'eq :key #'oddp) ⇒ NIL
(mismatch '(1 2 3 4 5 6) '(3 4 5 6 7) :start1 2 :end2 4) ⇒ NIL
The :test-not argument is deprecated.