Add example for "R meta operator used with list-associative operators"

Author: lukasvalle

doc/Language/operators.pod6

@@ -273,8 +273,9 @@ X<|R,reverse metaoperator>
 Any infix operator may be called with its two arguments reversed by
 prefixing with C<R>. Associativity of operands is reversed as well.
 
-    say 4 R/ 12;        # OUTPUT: «3␤»
-    say [R/] 2, 4, 16;  # OUTPUT: «2␤»
+    say 4 R/ 12;               # OUTPUT: «3␤»
+    say [R/] 2, 4, 16;         # OUTPUT: «2␤»
+    say [RZ~] <1 2 3>,<4 5 6>  # OUTPUT: «(41 52 63)␤»
 
 X<|»=«>
 X<|«=»>