I have a weird situation and I was wondering if anyone has a solution. I have a couple data classes ...

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[Nick Tiller]

I have a weird situation and I was wondering if anyone has a solution. I have a couple data classes from a shared library that are structured very similarly.

data class Foo(val width: Float, val height: Float, val x: Float, val y: Float)
data class Bar(val width: Float, val height: Float, val x: Float, val y: Float)

To construct them, I have to write something like

when(clss) 
    is Foo -> constructFoo()
    is Bar -> constructBar()

with each of those construct methods doing the exact same thing (setting the same variable names & types). Is there a structure or something in Kotlin that I can use to make this cleaner?

[karelpeeters]

Not really, there's always reflection as a last resort of course.

[Nick Tiller]

Yeah, that’s what I figured but I end up with a lot of repeating code so I figured I’d check

[Jordan Stewart]

You could potentially use a method reference, e.g. fun <T> construct(constructor: (Float, Float, Float, Float) -> T) = constructor(1f, 2f, 3f, 4f) so then constructFoo() becomes construct(::Foo). Not sure what constructFoo and constructBar do under the hood — if they do different things then they should probably be different methods! if they really do only differ by which constructor they call then this could be a way to reduce the duplication, but it’s also a bit more complicated so 🤷‍♂️ tradeoffs . . .

[Nick Tiller]

They’re copy-paste jobs with only the class being defined being the difference. I’ll play with this though! Thanks!