| dimensions | list of dimensions, or non-negative integer |
| element-type | a type specifier, default is T - any type |
| initial-element | a value, default is implementation dependent |
| initial-contents | an object |
| adjustable | a generalized boolean, default is NIL |
| fill-pointer | a valid fill pointer for the array, or T or NIL |
| displaced-to | an array or NIL, default is NIL |
| displaced-index-offset | a valid array row-major index for displaced arrays, default is 0 |
MAKE-ARRAY function creates a new array. Array can be adjustable if specified, that is its dimensions can be shrinked or enlarged by ADJUST-ARRAY function.
One-dimensional arrays can have a fill-pointer. Fill-pointer makes array look like as if it would be shorter with only as many elements as fill-pointer specifies - while elements at the real end of array a still retained. Such array can be very easily enlarged or shrinked in bounds of the real size just by setting fill-pointer which is very fast. Functions like VECTOR-PUSH, VECTOR-PUSH-EXTEND and VECTOR-POP make use of this.
Arrays can be displaced onto another array. Such array can have different dimensions and elements are shared on underlying row-major element order.
See also AREF, ELT, ADJUST-ARRAY, ARRAY-DIMENSION, ARRAY-DIMENSIONS, FILL-POINTER, ARRAY-IN-BOUNDS-P, ARRAY-ROW-MAJOR-INDEX, ARRAYP.
(make-array 5 :initial-element 'x) => #(X X X X X) (make-array '(2 3) :initial-element 'x) => #2A((X X X) (X X X)) (length (make-array 10 :fill-pointer 4)) => 4 (array-dimensions (make-array 10 :fill-pointer 4)) => (10) (make-array 10 :element-type 'bit :initial-element 0) => #*0000000000 (make-array 10 :element-type 'character :initial-element #\a) => "aaaaaaaaaa" (let ((a (make-array '(2 2) :initial-element 'x :adjustable t))) (adjust-array a '(1 3) :initial-element 'y) a) => #2A((X X Y))