Is there a way to sum multiple fields of a data cl...

# announcements

[MrNiamh]

Is there a way to sum multiple fields of a data class into a new instance? E.g.

private data class Quantity(val quantity: BigDecimal, val pendingQuantity: BigDecimal)
fun main(){
    val quantities = listOf(Quantity(BigDecimal.ONE, BigDecimal.ZERO), Quantity(BigDecimal.ZERO, BigDecimal.TEN), Quantity(BigDecimal.ONE, BigDecimal.ONE))
    println(quantities.sum()) //expecting Quantity(2, 11)
}

Obviously .sum() doesn’t work, just an example of what i’d like it to look like

[MrNiamh]

Oh reduce, duh.

fun main(){
    val quantities = listOf(Quantity(BigDecimal.ONE, BigDecimal.ZERO), Quantity(BigDecimal.ZERO, BigDecimal.TEN), Quantity(BigDecimal.ONE, BigDecimal.ONE))
    println(quantities.reduce { sum, element -> Quantity(sum.quantity + element.quantity, sum.pendingQuantity + element.pendingQuantity) }) //expecting Quantity(2, 11)
}

[Danish Ansari]

Thanks for sharing the knowledge

[hho]

or implement plus directly for the Quantity : https://pl.kotl.in/rTynXXmjd