I thought I could just use obj let MyObj obj but I think thi

Question

I thought I could just use obj let MyObj obj but I think this is giving me a function like a Supplier rather than the actual object

fitzoh · Answer

deinspanjer How about this ``` class MyObject val arg Any companion object fun create arg Any = arg let MyObject arg ```

gjesse · Answer

i think you want arg let

gjesse · Answer

let works just like map on any single object

deinspanjer · Answer

Okay I read the user guide on companion objects but I need to re read cause I obviously don t grok it yet

fitzoh · Answer

yep

fitzoh · Answer

updated

fitzoh · Answer

if you re used to the jvm it s basically a static method

deinspanjer · Answer

I tried changing it to a dumb if this == null null else wrap and my problem still persists so this let isn t the issue disappointed

deinspanjer · Answer

After this wrapped object is handed off to the Nashorn engine it tries to get a member of the wrapped object but it is getting a `Function0 lt java io Serializable gt ` instead of a string so I ve done something nasty somewhere

fitzoh · Answer

have you tried debugging printing it after creation but before passing it to Nashorn

gjesse · Answer

i am pretty sure that it should come out as an instance of MyObj

deinspanjer · Answer

Trying it is hard I need to try to port some of this experimentation over into the JUnit test I started for the Kotlin code

gjesse · Answer

it would be interesting to see the type in the debugger before it s passed to nashhorn maybe you ve wrapped the entire thing in an extra set of curly braces

deinspanjer · Answer

I thought exactly that but I haven t seen them yet if that is what I did

gjesse · Answer

the itellij debugger should show you interim inferred types it could help to break them down into explicit intermediate assignments amp step through with the debugger

deinspanjer · Answer

You mean like this slightly smiling face ``` final JsonElement jsonElement = data toJson final JsonObject asJsonObject = jsonElement getAsJsonObject final JSObject wrap = wrap asJsonObject final Object wrapMember = wrap getMember GatekeeperEndpointType log debug Lots of stuff ndata nasJsonObject nwrap n wrapMember data getClass getSimpleName data toString asJsonObject getClass getSimpleName asJsonObject toString wrap getClassName wrap toString ```

gjesse · Answer

something like that might work but i was more thinking set breakpoints in your code and use the intellij debugger

deinspanjer · Answer

Gee go for the easy stuff why don tcha slightly smiling face

deinspanjer · Answer

I just got a class cast exception that I think is showing me the culprit

deinspanjer · Answer

`java lang ClassCastException com jsonlogic JSObjectWrappersKt$wrap$1 cannot be cast to jdk nashorn api scripting JSObject`

deinspanjer · Answer

I was expecting that last guy to be a JSObject but it looks like it is my function0

deinspanjer · Answer

Did I do something wrong with this delegate ` override fun getMember name String Any = data name wrap `

deinspanjer · Answer

The intention is if you call getMember on my wrapped instance I get the member from the delegate object but then I wrap that member so it can be properly visible to the JS engine

deinspanjer · Answer

Aha maybe here is where I ve got those extra curly braces ``` fun JsonPrimitive wrap Any = if this == null null else if this isBoolean this bool else if this isNumber this number else this string ```

fitzoh · Answer

is it even possible for `this` to be null

deinspanjer · Answer

I think so

deinspanjer · Answer

because when calling wrap from the Java world it is via a static method that takes the receiver as an argument

deinspanjer · Answer

com jsonlogic JSObjectWrappersKt wrap something

deinspanjer · Answer

so I figured that Java could pass a null for something and hence I needed to guard against it

deinspanjer · Answer

Does that sound right

fitzoh · Answer

you re right cool

gjesse · Answer

it s the = sign

fitzoh · Answer

```fun Integer wrap String return if this == null nope else $this fun main args Array lt String gt val a = 5 val b Integer = null println a println b ```

deinspanjer · Answer

Yep I got rid of the braces after the = and it works

fitzoh · Answer

```5 null```

fitzoh · Answer

smile

deinspanjer · Answer

Well I shouldn t say works just on to the next bug

gjesse · Answer

lol yep = either use = or not both

deinspanjer · Answer

If you are interested here is the project I m working on I think it is in a somewhat useful state now

deinspanjer · Answer

deinspanjer · Answer

Thank you both for your help