Is there a better way to "toggle" an item in a col...

# stdlib

[Zoltan Demant]

Is there a better way to "toggle" an item in a collection? I usually do something along the lines of (pseudo) if(contains) remove else add but feel dirty everytime.

[Klitos Kyriacou]

If the collection is a MutableSet, you can do set.add(item) || set.remove(item). Not sure how readable that is, though.

[Zoltan Demant]

Thanks @Klitos Kyriacou, thats an approach I havent considered. I think Ill struggle understanding what it does if I come back to it at a later time 🥲

[Ayfri]

Just create a simple extension like

fun <T> MutableCollection<T>.toggle(property: T) {
    if (property in this) remove(property) else add(property)
}

fun main() {
    val myList = mutableListOf(1, 2, 3, 4)
	myList.toggle(3)
	myList.toggle(7)
	println(myList)
}
// which prints :
// [1, 2, 4, 7]

[Zoltan Demant]

@Ayfri If all else fails, thats what Ill do 👍🏽 I was sort of hoping that something like this was already available. Ive been reluctant to creating an extension function due to the fact that Im using this in a set of different modules, so Id need to create a module with this .. homer disappear

[Ayfri]

yes you could even create a library with a set of useful extensions like this that you use in every projects you need it :)