On another topic, Which would you choose? Goal: re...

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[bdawg.io]

On another topic, Which would you choose? Goal: reassign filters[property] if merging two nullable sets yields a non-empty set
1️⃣

val additional: Set<T>? = filterStates[requested]
if (additional is Set<*> && additional.isNotEmpty()) {
    val current: Set<T>? = filters[property]
    if (current is Set<*> && current.isNotEmpty()) {
        filters[property] = current.plus(additional)
    } else {
        filters[property] = additional
    }
}

2️⃣

filters[property].plusMaybe(filterStates[requested.value])?.let {
    filters[property] = it
}

fun <T : Any> Set<T>?.plusMaybe(other: Set<T>?): Set<T>? = (this ?: emptySet()).plus(other ?: emptySet()).takeIf { it.isNotEmpty() }

[diesieben07]

Why so complicated?

val new = (filterStates[requested] ?: emptySet()) + (filters[property] ?: emptySet())
if (new.isNotEmpty()) {
    filters[property] = new
}

[bdawg.io]

Ahh, that does look pleasing. While it does increase the assignments to filters[property] it wouldn’t be an issue in the case of a backing field

[diesieben07]

How does it increase the assignments?

[bdawg.io]

Currently, if filterStates[requested] yields null, it will short circuit from doing the assignment altogether

[diesieben07]

Ah, true. But that is not in line with the goal you posted 😄

[bdawg.io]

Right, which is why I mentioned it wouldn’t be an issue anyways 🙂

[bdawg.io]

@diesieben07 I think I’m going to use that one. Makes the code way more readable