Begin debugger

scmvm/vm.scm

@@ -127,7 +127,7 @@
 
 
 ;;; Execution
-(define* (make-vm #:key stack-size memory-size)
+(define* (make-vm #:key stack-size memory-size debugger)
   "Create a fresh VM, with optional stack and memory sizes"
   (define data-stack (if stack-size (make-stack stack-size) (make-stack)))
   (define ret-stack (if stack-size (make-stack stack-size) (make-stack)))
@@ -157,6 +157,8 @@
   (define (fetch-and-execute)
     (define exit? #f)
     (let lp ([op (fetch-byte)])
+      (when debugger
+        (debugger))
       (case (op-lookup op)
         [(push)
          (push data-stack (fetch-word))]