I would like to get a list of the values ordered by the map

Question

I would like to get a list of the values ordered by the map key ```val a = mapOf 2 to W 3 to V 1 to T ``` desired result ```val list = listOf T W V ``` I was reading you can do that using `sortedMap` but it doesn t come out on the IDE

eHelg · Answer

Probably something along ```val a = mapOf 2 to W 3 to V 1 to T val arranged = a values sorted ``` or ```val a = mapOf 2 to W 3 to V 1 to T val arranged = a values sortedBy your logic here ```

eHelg · Answer

My bad I read the question a bit wrong maybe you are looking for something like ```val a = mapOf 2 to W 3 to V 1 to T val arranged = a toSortedMap values```

Daniele B · Answer

Yes but `toSortedMap ` doesn t come up Maybe because I am using MultiPlaform

Daniele B · Answer

Yes I just checked it works on Android but not on CommonMain

Daniele B · Answer

Any alternative to it

eHelg · Answer

Poor mans substitue ```val a = mapOf 2 to W 3 to V 1 to T val arranged = a toList sortedBy it first map it second ``` But might make more sense digging into why sortedMap doesn t work

wbertan · Answer

thinking face Do you have TreeMap Because the `toSortedMap` extension just does this ```public fun lt K Comparable lt K gt V gt Map lt out K V gt toSortedMap SortedMap lt K V gt = TreeMap this ```

Daniele B · Answer

< eHelg> is `sortedMap` supported to work on MultiPlatform uhh that s weird It s not there

Daniele B · Answer

This is the definition of my map ```val myMap = MutableMap lt Int MyObject gt = mutableMapOf ```

eHelg · Answer

No idea never used MultiPlatform

wbertan · Answer

`toSortedMap` is only for JVM <https kotlinlang org api latest jvm stdlib kotlin collections >

Michael Böiers · Answer

Creating a sorted map just for the purpose of sorting seems wasteful to me Why not use a sequence of pairs sort them by key and map the value

Vampire · Answer

That s the solution eHelg suggested slightly smiling face

Michael Böiers · Answer

Yes but without creating a map in the process

Vampire · Answer

The map is the given thing

Michael Böiers · Answer

In the example yes

Michael Böiers · Answer

If the map is a given I d still use sequence over list

Tobias Berger · Answer

Be aware of this if you consider sequences here sorting a sequence still creates a list instance in the background and then builds a sequence on that list If you re fine with a sequence as an end result then you get a slight benefit from mapping the values out of the sorted entries But if you need to return any kind of collection using Sequences just creates unnecessary wrapper instances in this case

Michael Böiers · Answer

Considering that the wrapper instance is really cheap I d always try to avoid creating collection explicitly When you go the sequence route the implementation can decide whether to use a list or not Of course for optimum memory performance we could use a mutable list sort it in place and then map the values in place doing everything creating just one collection

Tobias Berger · Answer

Fair point although something like sorting is never possible on the fly in a sequence Using the collections directly shows more clearly what the code actually does