UGH, I think I know what to do, FUCKING LIST AND CONS CONFUCSING ME

AND WHY THE HELL DID THEHY USE CONS INSTEAD OF LIST ? oh god now I'm gonna have to review everything up until now to check if I am understanding this correctly... sigh but still I guess this is progress, by the way this version of the code is still not complete I just realized that if I kept only pushing correct stuff its not gonna be much of learning tbh.
zenAndroid · Feb 29, 2020 · 30ced8c · 30ced8c
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diff --git a/4_fourth/09-WhileUntil.scm b/4_fourth/09-WhileUntil.scm
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+; 2020-02-29 11:33 :: zenAndroid ::  Other solutions only implemented a subset, I will therefore probably implement while and until
+; Also, I saw Eli's solution and didn't like that it leaked the definition of the while-iter procedure to the outer namespace.
+
+
+; For reference:
+; (until <condition> <body>)
+
+(define (tagged-list? exp tag)
+  (if (pair? exp)
+      (eq? (car exp) tag)
+      false))
+
+(define (until? exp) (tagged-list? exp 'until))
+
+(define (until-condition exp) (cadr exp))
+
+(define (until-body exp) (cddr exp))
+
+(define (make-lambda parameters body)
+  (list 'lambda parameters body))
+
+(define (make-if predicate consequent alternative)
+  (list 'if predicate consequent alternative))
+
+(define (last-exp? seq) (null? (cdr seq)))
+(define (first-exp seq) (car seq))
+(define (rest-exps seq) (cdr seq))
+
+(define (sequence->exp seq)
+  (cond ((null? seq) seq)
+        ((last-exp? seq) (first-exp seq))
+        (else (make-begin seq))))
+
+(define (make-begin seq) (cons 'begin seq))
+
+(define (until-exp-handler exp)
+  (let ((condition (until-condition exp))
+        (body (until-body exp)))
+    (list
+      (make-lambda '()
+                   (sequence->exp 
+                     (list 'define (list 'loop)
+                           (make-if condition
+                                    (sequence->exp (list body (list 'loop)))
+                                    'while-loop-done)
+                           (list 'loop)))))))
+
+(define test-code
+  '(until
+     (< ii 5)
+     (display ii)
+     (set! ii (+ ii 1))))
+
+
+; ((lambda ()
+;    (define (loop)
+;      (if (< ii 5)
+;        (begin ((display ii) (set! ii (+ ii 1))) (loop))
+;        while-loop-done)))
+;  (loop))
+
+(define ii 0)
+
+((lambda ()
+   (begin (define (loop)
+            (if (< ii 5)
+              (begin (display ii) (set! ii (+ ii 1)) (loop))
+              'while-loop-done))(loop))))