Scala - Core Scala - Common Collections(for-loop, filter, map)

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 1.(No. 2464)を解いてみる。

その他参考書籍

• Programming Scala: Scalability = Functional Programming + Objects

Exercises 1.(No. 2464)

コード(Emacs)

#!/usr/bin/env scala-2.11

val odd_for_loop = for (n <- 0L to 19L if n % 2 == 1) yield n
println(odd_for_loop)

val odd_filter = (0L to 19L) filter (_ % 2 == 1)
println(odd_filter)

val odd_map = (0L to 9L) map (_ * 2 + 1)
println(odd_map)

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

$ ./sample1.scala 
Vector(1, 3, 5, 7, 9, 11, 13, 15, 17, 19)
Vector(1, 3, 5, 7, 9, 11, 13, 15, 17, 19)
Vector(1, 3, 5, 7, 9, 11, 13, 15, 17, 19)
$