pep-material: comparison progs/lecture2.scala

equal deleted inserted replaced

-:72f7dd1a3754
+:ead6089209ba
 // Scala Lecture 2
 //=================
-// Overloaded math operations
+// the pain with overloaded math operations
 (100 / 4)
 (100 / 3)
 // f1: (Int, Int) => Int
 // f2: List[String] => Option[Int]
 // ...
+// an aside: partial application
+def add(a: Int)(b: Int) : Int = a + b
+sum(add(2), 0, 2)
+sum(add(10), 0, 2)
+def add2(a: Int, b: Int) : Int = a + b
+sum(x => add2(2, x), 0, 2)
+sum(x => add2(10, x), 0, 2)
 // Function Composition
 //======================
 // How could Higher-Order Functions and Options be helpful?
 better_first_word("").map(duplicate)
 better_first_word("").map(duplicate).map(valid_msg)
-// Type abbreviations
-//====================
-// some syntactic convenience
-type Pos = (int, Int)
-type Board = List[List[Int]]
 // Implicits (Cool Feature)
 //=========================
 val B = (1 to 1000000 by 4).toSet
 time_needed(10, count_intersection(A, B))
 time_needed(10, count_intersection2(A, B))
+// Type abbreviations
+//====================
+// some syntactic convenience
+type Pos = (int, Int)
+type Board = List[List[Int]]
 // Sudoku