(define applicative-eval (lambda (exp) (cond ((atomic? exp) (eval-atomic exp)) ((special-form? exp)...
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Transcript of (define applicative-eval (lambda (exp) (cond ((atomic? exp) (eval-atomic exp)) ((special-form? exp)...
- Slide 1
- (define applicative-eval (lambda (exp) (cond ((atomic? exp) (eval-atomic exp)) ((special-form? exp) (eval-special-form exp)) ((list-form? exp) (eval-list exp)) ((value? exp) exp) ((application? exp) (let ((renamed-exp (rename exp))) ;
- Some examples > (applicative-eval 4) ((atomic? exp) (eval-atomic exp)) > (applicative-eval '(list 1 2)) ((atomic? exp) (eval-atomic exp)) ((special-form? exp) (eval-special-form exp)) ((list-form? exp) (eval-list exp)) ((atomic? exp) (eval-atomic exp)) (define list-form? (lambda (exp) (or (tagged-list? exp cons) (tagged-list? exp list) (tagged-list? exp append)))) (define eval-list (lambda (lst) (make-list (apply-primitive-procedure (applicative-eval (operator lst)) (list-of-values (operands lst))))) (define list-form? (lambda (exp) (or (tagged-list? exp cons) (tagged-list? exp list) (tagged-list? exp append)))) (define eval-list (lambda (lst) (make-list (apply-primitive-procedure (applicative-eval (operator lst)) (list-of-values (operands lst))))) (define eval-atomic (lambda (exp) (if (not (variable? exp)) exp (look-up-variable-value exp)) (define eval-atomic (lambda (exp) (if (not (variable? exp)) exp (look-up-variable-value exp)) ASP.scm: Substitution-core.scm: 2
- Slide 3
- > (applicative-eval '(lambda (x y) (+ x y 10))); ((atomic? exp) (eval-atomic exp)) ((special-form? exp) (eval-special-form exp)) (define eval-lambda (lambda (exp) (make-procedure (lambda-parameters exp) (lambda-body exp)))) (define eval-lambda (lambda (exp) (make-procedure (lambda-parameters exp) (lambda-body exp)))) (define lambda? (lambda (exp) (tagged-list? exp 'lambda) )) (define lambda? (lambda (exp) (tagged-list? exp 'lambda) )) Substitution-core.scm: (define eval-special-form (lambda (exp) (cond ((quoted? exp) (make-symbol exp)) ((lambda? exp) (eval-lambda exp)) (define eval-special-form (lambda (exp) (cond ((quoted? exp) (make-symbol exp)) ((lambda? exp) (eval-lambda exp)) (define special-form? (lambda (exp) (or (quoted? exp) (lambda? exp) (definition? exp) (if? exp) (begin? exp)))) (define special-form? (lambda (exp) (or (quoted? exp) (lambda? exp) (definition? exp) (if? exp) (begin? exp)))) ASP.scm: Substitution-core.scm: 3
- Slide 4
- ((application? exp) (let ((renamed-exp (rename exp)));
