How to convert set/println to string? - kotlin

Question

I'm trying to add set to email as text
//Data class
#Entity(tableName = "inventory")
data class InventoryDataClass(
#PrimaryKey(autoGenerate = true)
var id: Int,
#NonNull var itemNumber: String,
#NonNull val itemDescription: String,
val currentInventory: Int?,
#NonNull val optimalInventory: Int,
#NonNull val minInventory: Int
)
// getting list from room
val inventoryList by mainViewModel.getInventoryItems.collectAsState(initial = emptyList())
//converting list to set
val emailNumber = inventoryList.map { item ->
println("Item Number: ${item.itemNumber} | Item Description: ${item.itemDescription} | Current Inventory: ${item.currentInventory.toString()}")}.toSet()
I'm able to get the output I need:
I/System.out: Item Number: 123| Item Description: item1 | Current Inventory: 47
I/System.out: Item Number: 456| Item Description: item2 | Current Inventory: 8
...
How can I get it as a string and add it to my email as text? So far i'm only able to get Kotlin.Unit
Log.d(TAG, "InventoryMainScreen: $emailNumber")
//output
D/MainActivity: InventoryMainScreen: [kotlin.Unit]

Answer 1

You can use joinToString:
val logsString = inventoryList.joinToString(separator = "\n") { item ->
"Item Number: ${item.itemNumber} | Item Description: ${item.itemDescription} | Current Inventory: ${item.currentInventory.toString()}"
}

Answer 2

You can append to a StringBuilder:
//Output this:
//Item Number: 123| Item Description: item1 | Current Inventory: 47
//Item Number: 123| Item Description: item1 | Current Inventory: 47
val emailNumber = StringBuilder()
inventoryList.forEach { item ->
emailNumber.append("Item Number: ${item.itemNumber} | Item Description: ${item.itemDescription} | Current Inventory: ${item.currentInventory}").append("\n")
}
emailNumber.removeSuffix("\n")