Help with displaying only used fields in Object for JS backend

[Niminem]

Hey guys,
    
    
    type
        TestObj = object
            field1: int
            field2: float
            field3: string
    
    
    Run

I need to use an object, like the one above, as a parameter for quite a few 
javascript functions. In some cases, I don't want field`x` to be shown in the 
resulting javascript code- only the field/s I'm using.

Is there a way to only display the fields I'm actively using when passing an 
object like so: `wrappedFunction(TestObj(field1:9000))`

to produce: `function({field1:9000}`

rather than the default: `function({field1:9000, field2:0.0, field3:""})`

If I'm not clear enough please let me know