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| ANSI Common Lisp 15 Arrays 15.2 Dictionary of Arrays
15.2.10 aref | Accessor
  Syntax: aref array `&rest` subscripts element (setf (aref array `&rest` subscripts) new-element) Arguments and Values: array - an array. subscripts - a list of valid array indices for the array. element, new-element - an object. Description: Accesses the array element specified by the subscripts. If no subscripts are supplied and array is zero rank, aref accesses the sole element of array. aref ignores fill pointers. It is permissible to use aref to access any array element, whether active or not. Examples: If the variable `foo` names a 3-by-5 array, then the first index could be 0, 1, or 2, and then second index could be 0, 1, 2, 3, or 4. The array elements can be referred to by using the function aref; for example, `(aref foo 2 1)` refers to element (2, 1) of the array.
       (aref (setq alpha (make-array 4)) 3)  implementation-dependent
       (setf (aref alpha 3) 'sirens)   SIRENS
       (aref alpha 3)   SIRENS
       (aref (setq beta (make-array '(2 4)
                          :element-type '(unsigned-byte 2)
                          :initial-contents '((0 1 2 3) (3 2 1 0))))
              1 2)  1
       (setq gamma '(0 2))
       (apply #'aref beta gamma)  2
       (setf (apply #'aref beta gamma) 3)  3
       (apply #'aref beta gamma)  3
       (aref beta 0 2)  3
See Also: bit, char, elt, row-major-aref, svref, Section 3.2.1 Compiler Terminology Allegro CL Implementation Details: None.

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