2010-m1s1-compilation/meval.lisp

98 lines
2.2 KiB
Common Lisp

(load "match")
(defun get-env-num (num env)
(defun get-env-num-t (num env counter)
(cond ((= counter num) env)
((eq (aref env 0) nil) nil)
(T
(get-env-num-t num (aref env 0) (+ 1 counter))
)))
(get-env-num-t num env 0))
(defun map-meval (list env)
(mapcar (lambda (x) (meval x env)) list))
(defun meval-progn (list env)
(loop
for expr in list
do (meval expr env)
))
(defun meval (expr &optional env)
"Interprète le langage intermédiaire passé en paramètre."
(cond ((match :const (first expr))
(cdr expr))
((match :cvar (first expr))
(let ((sub-env (get-env-num (second expr) env)))
(if sub-env
(aref sub-env (third expr))
(error "The variable ~S is unbound" expr))))
((match :if (first expr))
(if (meval (second expr) env)
(meval (third expr) env)
(meval (fourth expr) env)))
((match :call (first expr))
(apply (symbol-function (cadr expr)) (map-meval (cddr expr) env)))
((match :progn (first expr))
(map-meval ())
(T
(error "form special ~S not yet implemented" (car expr)))))
;; Test unitaire
(load "test-unitaire")
(load "lisp2li")
(erase-tests meval)
(deftest (meval :const)
(meval (lisp2li 3 ()))
3)
(deftest (meval quote)
(meval (lisp2li '3 ()))
3)
(deftest (meval quote)
(meval (lisp2li ''3 ()))
3)
(deftest (meval quote)
(meval (lisp2li '''3 ()))
''3)
(deftest (meval :cvar)
(meval (lisp2li 'x '((x 0 2))) #(() 4 5 6))
5)
(deftest (meval :cvar)
(meval '(:cvar 1 2) #(#(() 7 8) 4 5 6))
8)
(deftest (meval :call)
(meval '(:call + (:const . 3) (:cvar 0 1)) #(() 4 5 6))
7)
(deftest (meval :call)
(meval '(:call list (:const . 3) (:const . 2)))
'(3 2))
(deftest (meval :if)
(meval '(:if (:const . T)
(:const . T)
(:const . nil)))
T)
(deftest (meval :if)
(meval '(:if (:call eq (:const . 1)
(:cvar 0 1))
(:const . T)
(:const . nil)) #(() 1 2 3))
T)
(deftest (meval defun)
(meval '(defun foo (x) x))
foo)
(deftest (meval defun)
(meval '(defun foo (x y z) (list x y z)))
foo)