Kotlin

Retrieving Single Elements

Swift

Retrieving by position

                  val numbers = linkedSetOf("one", "two", "three", "four", "five")
println(numbers.elementAt(3))    
​
val numbersSortedSet = sortedSetOf("one", "two", "three", "four")
println(numbersSortedSet.elementAt(0)) // elements are stored in the ascending order
                
                    let numbers = linkedSetOf("one", "two", "three", "four", "five")
print(numbers.elementAt(3))    
​
let numbersSortedSet = sortedSetOf("one", "two", "three", "four")
print(numbersSortedSet.elementAt(0)) // elements are stored in the ascending order
                  
                  val numbers = listOf("one", "two", "three", "four", "five")
println(numbers.first())    
println(numbers.last())
                
                    let numbers = listOf("one", "two", "three", "four", "five")
print(numbers.first())    
print(numbers.last())
                  
                  val numbers = listOf("one", "two", "three", "four", "five")
println(numbers.elementAtOrNull(5))
println(numbers.elementAtOrElse(5) { index -> "The value for index $index is undefined"})
                
                    let numbers = listOf("one", "two", "three", "four", "five")
print(numbers.elementAtOrNull(5))
print(numbers.elementAtOrElse(5) { index -> "The value for index $index is undefined"})
                  

Retrieving by condition

                  val numbers = listOf("one", "two", "three", "four", "five", "six")
println(numbers.first { it.length > 3 })
println(numbers.last { it.startsWith("f") })
                
                    let numbers = listOf("one", "two", "three", "four", "five", "six")
print(numbers.first { it.length > 3 })
print(numbers.last { it.startsWith("f") })
                  
                  val numbers = listOf("one", "two", "three", "four", "five", "six")
println(numbers.firstOrNull { it.length > 6 })
                
                    let numbers = listOf("one", "two", "three", "four", "five", "six")
print(numbers.firstOrNull { it.length > 6 })
                  
                  val numbers = listOf(1, 2, 3, 4)
println(numbers.find { it % 2 == 0 })
println(numbers.findLast { it % 2 == 0 })
                
                    let numbers = [1, 2, 3, 4]
print(numbers.find { $0 % 2 == 0 })
print(numbers.findLast { $0 % 2 == 0 })
                  

Random element

                  val numbers = listOf(1, 2, 3, 4)
println(numbers.random())
                
                    let numbers = [1, 2, 3, 4]
print(numbers.random())
                  

Checking existence

                  val numbers = listOf("one", "two", "three", "four", "five", "six")
println(numbers.contains("four"))
println("zero" in numbers)
​
println(numbers.containsAll(listOf("four", "two")))
println(numbers.containsAll(listOf("one", "zero")))
                
                    let numbers = listOf("one", "two", "three", "four", "five", "six")
print(numbers.contains("four"))
print("zero" in numbers)
​
print(numbers.containsAll(listOf("four", "two")))
print(numbers.containsAll(listOf("one", "zero")))
                  
                  val numbers = listOf("one", "two", "three", "four", "five", "six")
println(numbers.isEmpty())
println(numbers.isNotEmpty())
​
val empty = emptyList<String>()
println(empty.isEmpty())
println(empty.isNotEmpty())
                
                    let numbers = listOf("one", "two", "three", "four", "five", "six")
print(numbers.isEmpty())
print(numbers.isNotEmpty())
​
let empty = emptyList<String>()
print(empty.isEmpty())
print(empty.isNotEmpty())