Tweak some docs.

doc/site/lists.markdown

@@ -20,20 +20,20 @@ element you want. Like most languages, indexes start at zero:
 
     :::wren
     var hirsute = ["sideburns", "porkchops", "'stache", "goatee"]
-    hirsute[0] //> sideburns
-    hirsute[1] //> porkchops
+    System.print(hirsute[0]) //> sideburns
+    System.print(hirsute[1]) //> porkchops
 
 Negative indices counts backwards from the end:
 
     :::wren
-    hirsute[-1] //> goatee
-    hirsute[-2] //> 'stache
+    System.print(hirsute[-1]) //> goatee
+    System.print(hirsute[-2]) //> 'stache
 
 It's a runtime error to pass an index outside of the bounds of the list. If you
 don't know what those bounds are, you can find out using count:
 
     :::wren
-    hirsute.count //> 4
+    System.print(hirsute.count) //> 4
 
 ## Slices and ranges
 
@@ -41,7 +41,7 @@ Sometimes you want to copy a chunk of elements from a list. You can do that by
 passing a [range](values.html#ranges) to the subscript operator, like so:
 
     :::wren
-    hirsute[1..2] //> [porkchops, 'stache]
+    System.print(hirsute[1..2]) //> [porkchops, 'stache]
 
 This returns a new list containing the elements of the original list whose
 indices are within the given range. Both inclusive and exclusive ranges work
@@ -85,9 +85,9 @@ back. Doing so counts back from the size of the list *after* it's grown by one:
     :::wren
     var letters = ["a", "b", "c"]
     letters.insert(3, "d")   // OK: inserts at end.
-    System.print(letters)        //> [a, b, c, d]
+    System.print(letters)    //> [a, b, c, d]
     letters.insert(-2, "e")  // Counts back from size after insert.
-    System.print(letters)        //> [a, b, c, e, d]
+    System.print(letters)    //> [a, b, c, e, d]
 
 ## Removing elements