1 // Scala Lecture 2

     2 //=================

     3 

     4 

     5 // Option type

     6 //=============

     7 val lst = List(None, Some(1), Some(2), None, Some(3))

     8 

     9 lst.flatten

    10 Some(1).get

    11 

    12 val ps = List((3, 0), (3, 2), (4, 2), (2, 0), (1, 0), (1, 1))

    13 

    14 for ((x, y) <- ps) yield {

    15   if (y == 0) None else Some(x / y)

    16 }

    17