Scala - Core Scala - First-Class Functions(Assigning a Function, Type, Wildcard)

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 5.(First-Class Functions)、Exercises 5.(No. 1874)を解いてみる。

その他参考書籍

• Programming Scala: Scalability = Functional Programming + Objects

Exercises 5.(No. 1874)

コード(Emacs)

def square(m: Double) = m * m

// 明示的に型を記述
val sq : Double => Double = square

//　Wildcard operator を使用
val sq2 = square _

println(square(10))
println(sq(10))
println(sq2(10))

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

$ scala-2.11 sample5.scala
100.0
100.0
100.0
$