&gt; println() is not Iron request handler, you gave wrong example. Signature matters.<p>println is not relevant here it only shows the result of the call, the point is that you can use a method as a function, I expect the issue is elsewhere (but not having used Iron, I wouldn&#x27;t know where).<p>&gt; I don&#x27;t see how you can declare field if structure to have default value 65535, even with Default trait.<p>Implement Default then call it when instantiating struct: <a href="http:&#x2F;&#x2F;is.gd&#x2F;2YSoKd" rel="nofollow">http:&#x2F;&#x2F;is.gd&#x2F;2YSoKd</a><p>&gt; I posted opinion not to argue and really frustrating to see downvotes for opinion. Make discussion more constructive.<p>Er… I didn&#x27;t downvote you? I just replied to some of your objections which I assume is what you expected?