i have a marker interface ```interface RoomModel``` and an entity that implements this interface ``` Entity tableName = ContentAuthorModule ContentAuthorModule RoomModel ``` now if i have a ```List lt RoomModel gt ``` how do i check if its a ```List lt ContentAuthorModule gt ``` I tried to do ```roomModels is List lt ContentAuthorModule gt ``` ```override fun saveRoomModels roomModels List lt RoomModel gt when roomModels is List lt ContentAuthorModule gt gt contentAuthorModuleDao insertAll roomModels ``` but it gives my a syntax error that says ```Cannot check for instance of erased type List lt ContentAuthorModule gt ``` is there another way to do this

You can use `roomModels filterIsInstance lt ContentAuthorModule gt ` which will return a list of type `List lt ContentAuthorModule gt `

i have a marker interface ```interface RoomModel``` and an e kotlinlang #android

02/06/2020, 9:14 AM

i have a marker interface

interface RoomModel

and an entity that implements this interface

@Entity(tableName = "ContentAuthorModule")
ContentAuthorModule : RoomModel {}

now if i have a

List<RoomModel>

how do i check if its a

List<ContentAuthorModule>

I tried to do

roomModels is List<ContentAuthorModule>

override fun saveRoomModels(roomModels: List<RoomModel>) {
    when(roomModels) {
        is List<ContentAuthorModule> ->
            contentAuthorModuleDao.insertAll(roomModels)
    }
}

but it gives my a syntax error that says

Cannot check for instance of erased type : List<ContentAuthorModule>

is there another way to do this?

Ahmed Ibrahim

02/06/2020, 9:31 AM

roomModels.filterIsInstance<ContentAuthorModule>()

which will return a list of type

List<ContentAuthorModule>

You can't do an

is

because List is a generic, so during runtime the types are erased.