Im often in the situation that I have an enum clas...

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[Paul Woitaschek]

Im often in the situation that I have an enum class and that I want to have a value for each enum member. For example enum class BaseNutrient -> Map<BaseNutrient, Double>. Is there a more elegant way than using Basenutrient.values().associate { baseNutrient -> baseNutrient to 0.0 }
As I need that so frequently it feels like I’m overseeing sth in the stdlib

[Pavlo Liapota]

There is associateWith function where you need to return just a value instead of a pair.
So you can write list.associateWith { 0.0 }.
But this function is defined for Iterable only. So I usually define my own extension function:

inline fun <K, V> Array<out K>.associateWith(valueSelector: (K) -> V): Map<K, V> {
    return asIterable().associateWith(valueSelector)
}

[Amirul Zin]

Why not just declare it properly?

enum class BaseNutrient(val value:Double){
    NOODLE(100.0),
    CARROT(50.0),
  }

[Pavlo Liapota]

In my use-case this value is calculated. Something like this:

MyEnum.values().associateWith { foo(it) }

But if it is constant, then yes, property is the way to go.

[Paul Woitaschek]

Ok I’ll open a ticket for this, thanks

[Paul Woitaschek]

Damn https://youtrack.jetbrains.com/issue/KT-30372

[darkmoon_uk]

@Pavlo Liapota Is it calculated statically or dynamically? Either way, wouldn't an option be to just ascribe a function to each Enum, like:

enum class Nutrient(val value:(Nutrient)->Double){
    APPLE(myNutrientFunctionFruit),
    CARROT(myNutrientFunctionVeg),
    SWEDE(myNutrientFunctionVeg);

    val kiloJoules : Double get() = this.value()
  }