I have a `List<*> that I want to make a map ...

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[Stefan Peterson]

I have a `List<*> that I want to make a map out of based on the objects id. These `id`s are unique. I know I can use groupBy to create a map but that results in Map<Long, List<*>> when I would much rather have Map<Long, *>. Is there a nice idiomatic way to do this in K?

[Czar]

listOfObjects.mapTo(mutableListOf()) { it.id to it }.toMap()

[Czar]

Silly me, this:
listOfObjects.map { it.id to it }.toMap()

[Stefan Peterson]

Thanks dude! @natpryce already tipped me off to associateBy which is actually the most optimal solution I think.

[Nikky]

i think the correct function for this is list.associate { it.id to it }
associateBy is skipping the value part i think.. so i probably makes this even shorter

[gildor]

yes, associateBy is the shortest and most idiomatic way:

list.associateBy { it.id }

[Czar]

Uh, missed that one, thanks 🙂