Refactoring

mceval/ambeval.rkt

@@ -10,7 +10,8 @@
            "timing.rkt")
 
 (#%provide ambeval
-           driver-loop)
+           amb-driver-loop
+           amb-eval-program)
 
 (define (amb? exp) (tagged-list? exp 'amb))
 (define (amb-choices exp) (cdr exp))
@@ -192,20 +193,11 @@
 (define input-prompt ";;; Amb-Eval input:")
 (define output-prompt ";;; Amb-Eval value:")
 
-(define (driver-loop)
+(define (amb-driver-loop)
   (define env (setup-environment))
   ;; Need to pass success and failure continuations to ambeval, so
   ;; will probably need a different eval-program.
-  (eval-program amb-utilities-program
-                (lambda (exp env)       ; Evaluate exp using ambeval
-                                        ; passing in appropriate
-                                        ; continuations
-                  (ambeval exp
-                           env
-                           (lambda (value fail) value)
-                           (lambda () 'failed)))
-                user-print
-                env)
+  (amb-eval-program-in-env amb-utilities-program env)
   (define (internal-loop try-again)
     (prompt-for-input input-prompt)
     (let ((input (read)))
@@ -226,12 +218,12 @@
                        (announce-output
                         ";;; There are no more values of")
                        (user-print input)
-                       (driver-loop)))))))
+                       (amb-driver-loop)))))))
   (internal-loop
    (lambda ()
      (newline)
      (display ";;; There is no current problem")
-     (driver-loop))))
+     (amb-driver-loop))))
 
 
 
@@ -252,7 +244,21 @@
     (make-combination (make-lambda (map let-var bindings)
                                    (let-body exp))
                       (map let-val bindings))))
-                     
+
+(define (amb-eval-program-in-env program env)
+  (eval-program program
+                (lambda (exp env)
+                                (ambeval exp
+                                         env
+                                         (lambda (value fail) value)
+                                         (lambda () 'failed)))
+                user-print
+                env))
+
+(define (amb-eval-program program)
+  (define env (setup-environment))
+  (amb-eval-program-in-env amb-utilities-program env)
+  (amb-eval-program-in-env program env))
 
 
 'AMB-EVALUATOR-LOADED