Start to work on 5.25 and finish syntax error in eceval

ex-5_23-xx.scm

@@ -39,5 +39,16 @@
 (assert (get-register-contents eceval 'val) 10)
 
 
-(display "\nex-5.25\n")
+(display "\nex-5.25 - lazy-evaluation\n")
+
+(set-register-contents! eceval 'exp
+  '(begin
+     (define (try a b)
+       (if (= a 0) 1 b))
+     (try 0 (/ 1 1))))
+(start eceval)
+(assert (get-register-contents eceval 'val) 1)
+
+
+(display "\nex-5.26\n")
 

misc/sicp-eceval.scm

@@ -68,7 +68,7 @@
    (list 'define-variable! define-variable!)
    (list 'empty-arglist empty-arglist)
    (list 'extend-environment extend-environment)
-   (list 'get-global-environment get-global-environment))
+   (list 'get-global-environment get-global-environment)
    (list 'last-operand? last-operand?)
    (list 'lookup-variable-value lookup-variable-value)
    (list 'make-procedure make-procedure)
@@ -92,7 +92,7 @@
    (list 'cond? cond?)
    (list 'let->combination let->combination)
    (list 'let? let?)
-   )
+   ))
 
 (define eceval
   (make-machine