Add: sol 5.50

Author: codybartfast

test/code/ch5/ex5.50/ec-evaluator-50.sicp

@@ -158,8 +158,10 @@
         (list 'cdddr cdddr)
         (list 'apply-in-underlying-scheme apply-in-underlying-scheme)
         ;; Additional primitive procedures installed in the MC-evaluator
+        (list '+ +)
         (list '- -)
         (list '* *)
+        (list '< <)
         (list 'equal? equal?)
         ))
 

test/code/ch5/ex5.50/ex5.50-cbf.sicp

@@ -16,4 +16,3 @@
 
 (display "Starting matacirculator evaluator REPL ...")(newline)
 (start machine)
-;machine

test/code/ch5/ex5.50/machine-50.sicp

@@ -130,25 +130,17 @@
         (set! write-trace write-null))
       (define (execute-proceed check-break)
         (let ((insts (get-contents pc)))
-(display-line "execute-proceed, insts: ")(display (length insts))
-(display-line (car insts))
-(display-line "============")
-          (cond (  (begin (display-line ">>>> cond")    (null? insts))
-(display-line "done: ")
+          (cond ((null? insts)
                  'done)
-                (  (begin (display-line "(<<<< symb 1)")  (car insts) (display-line "(<<<< symb 2)") (display-line (symbol? (car insts))) (display-line "(<<<< symb 3)")    (symbol? (car insts)))
-(display-line "symbol")
+                ((symbol? (car insts))
                  (write-trace (car insts))
                  (advance-pc pc)
                  (execute))
 
                 (else
-(display-line "execute-proceed-else")
                  (write-trace (instruction-text (car insts)))
                  ((instruction-execution-proc (car insts)))
-(display-line "execute-proceed-else-set")
                  (set! inst-count (+ inst-count 1))
-(display-line "execute-proceed-else-execute")
                  (execute)))))
       (define (proceed) (execute-proceed false))
       (define (execute) (execute-proceed true))

test/code/ch5/ex5.50/mc-evaluator-50-exp.sicp

@@ -280,9 +280,11 @@
                  (map proc (cdr items)))))
 
      (define primitive-procedures
-       (list (list '= =)
-             (list '* *)
+       (list (list '+ +)
              (list '- -)
+             (list '* *)
+             (list '= =)
+             (list '< <)
              (list 'cons cons)
              (list 'list list)
              (list 'equal? equal?)