What would be an idiomatic way to convert a `Map&l...

# stdlib

[gregorbg]

What would be an idiomatic way to convert a Map<K, List<V>> into a Map<V, K> such that every entry in the List<V> becomes associated with its original key K? ({"foo": [1, 2, 3]} becomes {1: "foo", 2: "foo", 3: "foo"} )

[gregorbg]

Currently I have:

myMap.entries
  .flatMap { e ->
    e.value.map { it to e.key }
  }.toMap()

which I don't consider particularly intuitive

[Dico]

myMap.entries.fold(HashMap()) { m, (k, v) -> v.associateWithTo(m) { k } }

[Dico]

Something like that perhaps?

[Dico]

Probably doesn't compile but you get the drill

[jimn]

myMap.entries.map{(k,v)->v.map{it to k}}.toMap()

[jimn]

oh my bad missed the List<V> explicit param.