;; Normal evaluation
(define (f x) (+ x 1))
(f 3)

;; Constants
,(define f 3)
(list ,f 5)

;; Separate namespaces
(f ,f)

;; Macros
,(define (inc! x) `(set! ,x (+ ,x 1)))
(define x 1)
,(inc! `x)
x

;; See what gets evaluated
(,inc! `x)

;; Local macro
,(let ((inc! (lambda (x) `(set! ,x (+ ,x 10)))))
   `(begin ,(inc! `x) x))
,(inc! `x)
x

;; Meta-meta-level simple game
,,(define (inc! x) ``(set! ,,x (+ ,,x 1)))
(,,inc! ``x)
,(,inc! ``x)
,,(inc! ``x)

;; Example from "Run-time Code Generation and Modal-ML"
(define poly1 '(1 2 3 4))

(define (eval-poly x p)
  (if (null? p)
    0
    (+ (car p) (* x (eval-poly x (cdr p))))))
(eval-poly 2 poly1)

(define (spec-poly p)
  (if (null? p)
    (lambda (x) 0)
    (let ((polyp (spec-poly (cdr p))))
      (lambda (x) (+ (car p) (* x (polyp x)))))))
((spec-poly poly1) 2)

,(define (comp-poly p)
   (if (null? p)
     (lambda (x) `0)
     (let ((polyp (comp-poly (cdr p))))
       (lambda (x) `(+ ,(car p) (* ,x ,(polyp x)))))))
((,comp-poly poly1) 2)
(,(comp-poly `(1 2 3 4)) 2)
,((comp-poly `(1 2 3 4)) 2)

,(define (comp-poly p x)
   (if (null? p)
     `0
     (let ((polyp (comp-poly (cdr p) x)))
       `(+ ,(car p) (* ,x ,polyp)))))
(,comp-poly poly1 2)
,(comp-poly `(1 2 3 4) 2)



(define-macro make-inc-n
  (lambda (n)
    (list 'lambda (list 'x)
          (list 'list ''set! 'x (list 'list ''+ 'x n)))))
(define-macro make-inc-n
  (lambda (n)
    `(lambda (x)
       `(set! ,x (+ ,x ,,n)))))
(define-macro inc3! (make-inc-n 3))
(define x 3)
(inc3! x)







  ;; Constant definition
  ,(define c 3)
  (list ,c 5)

  ;; Macro definition & usage
  ,(define inc! (lambda (x) `(set! ,x (+ ,x 1))))
  ,(inc! `x)

  ;; this applies the `macro' function on some syntax
  (,inc! `x)
    --> (set! x (+ x 1))

  ;; Local macro
  ,(let ((inc! (lambda (x) `(set! ,x (+ ,x 10)))))
     (inc! `x))

  ;; Meta-meta-level simple game
  ,,(define inc! (lambda (x) ``(set! ,,x (+ ,,x 1))))
  (,,inc! ``x)
    --> `(set! ,`x (+ ,`x 1))
  ,(,inc! ``x)
    --> (set! x (+ x 1))
  ,,(inc! ``x)
    ; actually incrementing x

  ;; A simple meta-meta macro
  ,,(define make-inc-n
      (lambda (n)
        `(lambda (x)
           `(set! ,x (+ ,x ,,n)))))
  ,(define inc3! ,(make-inc-n ``3))
  (define x 3)
  ,(inc3! `x)

;;Local variables:
;;hide-local-variable-section: t
;;enable-local-eval: t
;;eval:(autoload 'meta-highlight "meta")
;;eval:(make-local-hook 'find-file-hooks)
;;eval:(add-hook 'find-file-hooks '(lambda () (local-set-key [f9] 'meta-highlight) (local-set-key [(control f9)] 'meta-print)) t t)
;;End: