Scala

Operaciones de Colecciones

Operaciones funcionales: map, filter, fold, groupBy.

#collections#functional

Code

scala

val nums = (1 to 10).toList

// map / filter
val doubled = nums.map(_ * 2)
val evens = nums.filter(_ % 2 == 0)

// fold / reduce
val sum = nums.foldLeft(0)(_ + _)
val product = nums.reduce(_ * _)

// groupBy
val grouped = nums.groupBy(_ % 3)
// Map(0 -> List(3,6,9), 1 -> List(1,4,7,10), 2 -> List(2,5,8))

// flatMap / flatten
val nested = List(List(1,2), List(3,4))
nested.flatten       // List(1,2,3,4)
nested.flatMap(_.map(_ * 10))  // List(10,20,30,40)

All snippets