I'm writing a method that other people on my team ...

# getting-started

[Colton Idle]

I'm writing a method that other people on my team are going to use and the method has to accept a mapOf size 1. Is there any way to enforce that?

Basically my method is

fun myFunction(event: Map)

but technically right now it can be mis-used because you can add more than 1 item in the map. Ideas?

[ephemient]

isn't that just a Pair?

[Colton Idle]

Is it? Lets see. FWIW. I tried Key.Entry with no luck. and I'm boxed into using a map because thats what i need for a moshi serialization that im doing (my question from yest pointed me to a map #squarelibraries)

[ephemient]

if you want it to serialize like a map, you'll need custom logic. I haven't used Moshi in a long time though, don't remember how that's done

[Colton Idle]

dang. yeah. Just tried a pair and it seraializes the first and second property

[Colton Idle]

I thought Map.Entry might do it, but seems like I can't just init a Map.Entry

[ephemient]

there is AbstractMap.SimpleEntry on JVM but that won't serialize to what you want either

[Colton Idle]

thanks. back to the drawing board. backend team be damned.

[lazynoda]

Couldn't you get the Pair<A, B> and internally transform into a Map<A, B> with mapOf(pair)?

fun myFunction(event: Pair<String, Any>) {
    val mapEvent = mapOf(event)
    // Go to Moshi...
}

[Colton Idle]

yeah. i think thats what im going to fallback to. i haven't tried it yet, but pappering over the issue here makes sense i think

[Youssef Shoaib [MOD]]

In general, a function should probably expose exactly what it needs as parameters, and then only internally transform them for any quirks (because those are implementation details)

[Rob Elliot]

FWIW my experience has been that I've generally ended up refactoring fun myFunction(pair: Pair<String, Any>) to fun myFunction(key: String, value: Any) .

It lets you give the two values sensible parameter names in the function, reduces the amount of generics in the type signatures, and even if the caller has a Pair it's trivial to decompose it.