Scala - Core Scala - Expressions and Conditionals(if...else blocks, match expression)

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

開発環境

• OS X Yosemite - 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 3.(Expressions and Conditionals)、Exercises 2.(No. 1081)を解いてみる。

その他参考書籍

• Programming Scala: Scalability = Functional Programming + Objects

Exercises 2.(No. 1081)

コード(Emacs)

import scala.io.StdIn.readLine;

var s = readLine(">> ")

while (s != "quit") {
  val amount : Double = s.toDouble
  if (amount > 0) println("greater")
  else if (amount == 0) println("same")
  else if (amount < 0) println("less")

  amount match {
    case x if x > 0 => println("greater")
    case x if x == 0 => println("same")
    case x if x < 0 => println("less")
    case _ => println("?")
  }

  s = readLine(">> ")
}

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

$ scala-2.11 sample2.scala
>> 1.2
greater
greater
>> 0
same
same
>> -1.2
less
less
>> quit
$