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|
;;;; l-system.lisp
#|
(ql:quickload :l-system)
|#
(in-package #:l-system)
;;; "l-system" goes here. Hacks and glory await!
(defun iterconcat (fn list)
"Applies fn on each element of list, and concatenate a copy of the resulting lists."
(iter (for item in list)
(appending (funcall fn item))))
(defun make-case-clause (keys value)
"Make one CASE clause mapping a list of KEYS to one VALUE"
`((,@keys) ',value))
(defun make-case-clauses-from-rules (rules)
"Makes a list of CASE clauses from the RULES."
(mapcar (lambda (rule) (make-case-clause (list (first rule)) (rest rule)))
rules))
(defun generate-l-system (rules)
"Make lambda Lindenmayer system"
`(lambda (atom) (case atom
,@(make-case-clauses-from-rules rules)
(t (list atom)))))
(defmacro l-system (&rest rules)
(generate-l-system rules))
(defun iter-l-system (rules axiom depth)
(iter (repeat depth)
(with result = axiom)
(setf result
(iterconcat rules
result))
(finally (return result))))
|
