Install explicit-control evaluator

ex-5_23-xx.scm

@@ -1,5 +1,17 @@
 (load "util.scm")
 (load "misc/sicp-regsim.scm")
+(load "misc/sicp-eceval.scm")
 
-(display "\nex-5.23\n")
+(define the-global-environment (setup-environment))
+(set-register-contents! eceval 'exp '(+ 1 2))
+(start eceval)
+(assert (get-register-contents eceval 'val) 3)
+
+(display "\nex-5.23 - derived-expressions\n")
+
+
+(display "\nex-5.24\n")
+
+
+;(display "\nex-5.25\n")