+ (let ([expanded (expand-pattern-matches prog)])
+ (cadr (check (init-adts-env expanded) (normalize (program-body expanded))))))
+
+
+ ; before passing annotated types onto codegen
+ ; we need to restore the pre-normalization structure
+ ; (this is important for function arity etc)
+(define (denormalize orig normed)
+
+ (define (collapse-lambdas n x)
+ (case n
+ [0 x]
+ [else
+ (let* ([inner-lambda (lambda-body (ann-expr x))]
+ [arg (lambda-arg (ann-expr x))]
+ [inner-collapsed (ann-expr (collapse-lambdas (- n 1) inner-lambda))])
+ `((lambda ,(cons arg (lambda-args inner-collapsed))
+ ,(lambda-body inner-collapsed)) : ,(ann-type x)))]))
+
+ (define (collapse-apps n x)
+ (case n
+ [-1 (error #f "nullary functions not handled yet")]
+ [0 x]
+ [else
+ (let* ([inner-app (car (ann-expr x))]
+ [inner-collapsed (collapse-apps (- n 1) inner-app)])
+ `(,(append (ann-expr inner-collapsed) (cdr (ann-expr x))) : ,(ann-type x)))]))
+
+ (case (ast-type orig)
+ ['lambda
+ (let ([collapsed (collapse-lambdas (- (length (lambda-args orig)) 1) normed)])
+ `((lambda ,(lambda-args (ann-expr collapsed))
+ ,(denormalize (lambda-body orig)
+ (lambda-body (ann-expr collapsed)))) : ,(ann-type collapsed)))]
+ ['app
+ (let ([collapsed (collapse-apps (- (length orig) 2) normed)])
+ `(,(map (lambda (o n) (denormalize o n)) orig (ann-expr collapsed))
+ : ,(ann-type collapsed)))]
+ ['let
+ `((let ,(map (lambda (o n) (list (car o) (denormalize (cadr o) (cadr n))))
+ (let-bindings orig)
+ (let-bindings (ann-expr normed)))
+ ,@(map (lambda (o n) (denormalize o n))
+ (let-body orig)
+ (let-body (ann-expr normed)))) : ,(ann-type normed))]
+ ['if `((if ,@(map denormalize (cdr orig) (cdr (ann-expr normed))))
+ : (ann-type normed))]
+ [else normed]))
+
+(define ann-expr car)
+(define ann-type caddr)
+
+ ; prerequisites: expand-pattern-matches