diff options
| -rw-r--r-- | hw09.scm | 40 |
1 files changed, 6 insertions, 34 deletions
@@ -65,15 +65,6 @@ (type-exp ("bool") bool-type-exp) (type-exp (identifier) tid-type-exp) (type-exp ("(" (separated-list type-exp "*") "->" type-exp ")") proc-type-exp) - - ; (4.3) list stuffs - (primitive ("cons") cons-prim) - (primitive ("car") car-prim) - (primitive ("cdr") cdr-prim) - (primitive ("list") list-prim) - (primitive ("emptylist") empty-list-prim) - (primitive ("null?") null-prim) - )) ; ------------------------------------------------------------ @@ -90,9 +81,7 @@ ; named atomic type (atomic-type (name symbol?)) ; procedure type (parameter types and result type) - ( proc-type (arg-types (list-of type?)) (result-type type?)) - ( list-type (item-type type?) ) - ) + ( proc-type (arg-types (list-of type?)) (result-type type?)) ) ; primitive types (define int-type (atomic-type 'int )) @@ -188,7 +177,7 @@ (lambda (rands tenv) (map (lambda (expr) (type-of-expression expr tenv)) rands) )) -(define type-of-primitive + (define type-of-primitive (lambda (prim) (cases primitive prim ( add-prim () (proc-type (list int-type int-type) int-type)) @@ -196,15 +185,7 @@ (mult-prim () (proc-type (list int-type int-type) int-type)) (incr-prim () (proc-type (list int-type) int-type)) (decr-prim () (proc-type (list int-type) int-type)) - (zero-prim () (proc-type (list int-type) bool-type)) - - (cons-prim () 1) - (car-prim () 1) - (cdr-prim () 1) - (list-prim () 1) - (empty-list-prim () 1) - (null-prim () 1) - ))) + (zero-prim () (proc-type (list int-type) bool-type)) ))) (define type-of-proc-expr (lambda (texps ids body tenv) @@ -372,11 +353,9 @@ (lambda (ty) (cases type ty (atomic-type (name) name) - (proc-type (arg-types result-type) + ( proc-type (arg-types result-type) (append (arg-types-to-external-form arg-types) '(->) - (list (type-to-external-form result-type)) )) - (list-type (item-type) 'asdf) - ))) + (list (type-to-external-form result-type)) ))))) (define arg-types-to-external-form (lambda (types) @@ -426,7 +405,7 @@ ))) -(define eval-program + (define eval-program (lambda (prog) (cases program prog (stmt-prog (body) (eval-expression body (empty-env))) ))) @@ -452,13 +431,6 @@ (incr-prim () (+ (car args) 1)) (decr-prim () (- (car args) 1)) (zero-prim () (if (zero? (car args)) 1 0)) - - (cons-prim () (cons (car args) (cadr args))) - (car-prim () (car args)) - (cdr-prim () (cdr args)) - (list-prim () args) - (empty-list-prim () '()) - (null-prim () ((if (null? (args)) 1 0))) ))) ; ------------------------------------------------------------ |