Scala - Core Scala - Common Collections(factors, List, flatMap)

Learning Scala:
Practical Functional Programming for the JVM
(O'Reilly Media)
Jason Swartz (著)

開発環境

• OS X El Capitan - Apple (OS)
• Emacs (Text Editor)
• Scala (プログラミング言語)

Learning Scala: Practical Functional Programming for the JVM (Jason Swartz (著)、O'Reilly Media)のPart Ⅰ. (Core Scala)、Chapter 6.(Common Collections)、Exercises 2.(No. 2464)を解いてみる。

その他参考書籍

• Programming Scala: Scalability = Functional Programming + Objects

Exercises 2.(No. 2464)

コード(Emacs)

#!/usr/bin/env scala-2.11

def factors(num:Int) = (2 until num) filter (num % _ == 0)

println(factors(15))

def flatMapFactors(nums:List[Int]) = nums flatMap factors

println(flatMapFactors(List(9, 11, 13, 15)))

入出力結果(Terminal, REPL(Read, Eval, Print, Loop))

$ ./sample2.scala
Vector(3, 5)
List(3, 3, 5)
$