You have two choices:
- The first and most performant is to use
associateBy
function that takes two lambdas for generating the key and value, and inlines the creation of the map:
val map = friends.associateBy({it.facebookId}, {it.points})
- The second, less performant, is to use the standard
map
function to create a list ofPair
which can be used bytoMap
to generate the final map:
val map = friends.map { it.facebookId to it.points }.toMap()