Given the following code extracted from Kotlin Koans:
fun Shop.findAnyCustomerFrom(city: City): Customer? {
// Return a customer who lives in the given city, or null if there is none
return customers.firstOrNull { it.isFrom(city) }
}
My own solution used customers.find. Both work in the koan scenario.
The documentation for firstOrNull and find seem to be very similar.
What is the difference between these two functions?