Is there anyway in Kotlin to have two constructors in class

Question

Is there anyway in Kotlin to have two constructors in class with both having lists as an argument but with different types in them For example ```constructor aList List lt A gt Main constructor constructor bList List lt B gt this bList toListA ``` I get the following ```Platform declaration clash The following declarations have the same JVM signature Ljava util List V ``` How do I distinguish between them

mkrussel · Answer

I don t think you can with constructors Instead you probably need to create factory methods and use the JvmName annotation to make the name different for Java callers You can use the name of the class for the factory methods if you want it to look like a constructor Probably keep the List lt A gt one as a constructor and make the List lt B gt a function

rtsketo · Answer

Thanks Came to the same conclusion just a minute ago You can even make the function look as a constructor by overriding the `invoke` operator Still it kind of feels like a hack to me Pretty weird Kotlin doesn t offer a better solution

CLOVIS · Answer

To my knowledge it is considered bad practice to use Companion invoke to mimic a constructor The better practice is to have a top level function that has the same name as the class with the capitals and everything

CLOVIS · Answer

for example the `List` factory in the standard library

CLOVIS · Answer

Also for the lack of better solution Project Valhalla will bring runtime reified generics to the JVM maybe then

ephemient · Answer

as far as I m aware there is still no spec for generic specialization Valhalla has implemented L world types but not <https openjdk java net jeps 218>

Dominaezzz · Answer

I d love top level functions more if intellij didn t remove the class icon from the Kotlin file

y9san9 · Answer

Haha felt something same at the beginning of my Kotlin programming Now this problem in my mind fixed and it s not problem Additionally the idea now does not provide a `function name` warning in case if such functions have the same return type as its name

CLOVIS · Answer

< Dominaezzz> then you can put it in the companion object and `import static` it Honestly though you shouldn t architecture your code just so you have a specific icon on your screen especially when that stops you from using one of the most important features of the language

rtsketo · Answer

OCD gift and curse at the same time