Common Lisp/Reference/defstruct

The defstruct construct declares a new user-defined data type which has a fixed number of named components. It also creates structure constructor. Example The following exampleFundamentals of CLOS by Nick Levine, Ravenbrook Limited, 2003-07-15 declares a Lisp structure with the symbol point and three slots referenced by the symbols x, y, and z. Here constructor is named make-point. (defstruct point x y z) ; define structure (defvar my-point) ; define var (setf my-point (make-point :x 3 :y 4 :z 12)) ; set value of slots of var (point-x my-point) ; access to slots ;; объявление и инициализация структуры (initiating of structure) (defstruct 3dpoint (x 0) (y 0) (z 0)); ;; обязательно превращем все это в динамическую переменную (defvar *my-points* (make-array '(1000000) :element-type '3dpoint)) ;; получение случайного числа (get random number from interval) (defun random-from-range (start end) (+ start (random (+ 1 (- end start))))) ;; функция заполнения массива структур (set values in array of structures) (defun setf-my-points (*my-points*) (declare (special *my-points*)) (loop for i from 1 to 1000000 do (progn (print i) (setf (aref *my-points* i) (make-3dpoint :x (random-from-range 1 100) :y (random-from-range 100 200) :z (random-from-range 300 400))) ) ) ) ;; заполняем случайными значениями 1 (call function that set value in array of structures) (print (time (setf-my-points *my-points*))) ;; получаем доступ к случайному значению (1 1000000) access to random ID record (3dpoint-x (aref *my-points* (random-from-range 1 1000000))) ;; смотрим время доступа... (see time) (print (time (3dpoint-x (aref *my-points* (random-from-range 1 1000000))))) See also defclass s# macro References defstruct