diff --git a/OscCommentMacroListener.py b/OscCommentMacroListener.py
index 4a96c04..d596f68 100644
--- a/OscCommentMacroListener.py
+++ b/OscCommentMacroListener.py
@@ -25,7 +25,7 @@ def num(string):
 
 
 def _master_go(self, ctx):
-    if ctx.number.value is not None:
+    if ctx.number is not None:
         print("GO MASTER doesn't support goto.  "
               + "Cue number " + str(ctx.number.value) + " will be ignored.")
 
@@ -217,7 +217,6 @@ class OscCommentMacroListener(CommentMacroListener):
             return -1
 
         print("Exiting Macro")
-        return 1
 
     def enterMaster(self, ctx: CommentMacroParser.MasterContext):
         ctx.targets = []
@@ -236,9 +235,15 @@ class OscCommentMacroListener(CommentMacroListener):
     def exitSpan(self, ctx: CommentMacroParser.SpanContext):
         number1 = ctx.children[0].value
         number2 = ctx.children[2].value
-        if isinstance(ctx.parentCtx, CommentMacroParser.TargetContext):
-            for i in (range(min(number1, number2), max(number1, number2) + 1)):
-                ctx.parentCtx.targets.append(i)
+        if (isinstance(number1, int) and isinstance(number2, int)):
+            if isinstance(ctx.parentCtx, CommentMacroParser.TargetContext):
+                minimum = min(number1, number2)
+                maximum = max(number1, number2)
+                for i in (range(minimum, maximum + 1)):
+                    ctx.parentCtx.targets.append(i)
+        else:
+            print("ERROR: Spans must be ranged with intigers.")
+            ctx.parentCtx.targets.append(-1)
 
     def enterTarget(self, ctx: CommentMacroParser.TargetContext):
         ctx.targets = []