rework eval loop to unwrap lists when function calls return

cmd/repl.go

@@ -106,7 +106,13 @@ func main() {
             ast.PrintSExprsIndividually(userInput)
         }
 
-        result := userInput.Eval(funcs, vars)
-        fmt.Println(result.String() + "\n")
+        result, unwrap := userInput.Eval(funcs, vars)
+        if unwrap {
+            result = result.Inner.(*ast.Token)
+        }
+        for i := result; i != nil; i = i.Next {
+            fmt.Printf(i.String() + " ")
+        }
+        fmt.Printf("\n")
     }
 }