Sign In Start Free Trial
Account

Add to playlist

Create a Playlist

Modal Close icon
You need to login to use this feature.
  • Professional Scala
  • Toc
  • feedback
Professional Scala

Professional Scala

By : Hartmann, Shevchenko
4.2 (13)
close
Professional Scala

Professional Scala

4.2 (13)
By: Hartmann, Shevchenko

Overview of this book

This book teaches you how to build and contribute to Scala programs, recognizing common patterns and techniques used with the language. You’ll learn how to write concise, functional code with Scala. After an introduction to core concepts, syntax, and writing example applications with scalac, you’ll learn about the Scala Collections API and how the language handles type safety via static types out-of-the-box. You’ll then learn about advanced functional programming patterns, and how you can write your own Domain Specific Languages (DSLs). By the end of the book, you’ll be equipped with the skills you need to successfully build smart, efficient applications in Scala that can be compiled to the JVM.
Table of Contents (10 chapters)
close

Functions

In this section, we will introduce the fundamentals of functional programming, such as function values and high-order functions.

Function Values

What is a function? We are familiar with methods, which must be defined in a scope (class or objects):

  def f1(x:Int, y:Int): Int =  x + y

In Scala, we can also define a function value:

   val f2: (Int,Int) => Int = (x,y) => (x+y).

Here, we define the function value, with a type of (Int,Int) => Int. Of course, as with all type declarations, the type can be omitted if it can be deduced from the context. So, an alternative syntax for this can be:

   val f2 = (x:Int,y:Int) => (x+y).

Both f1(1,2) and f2(1,2) will force evaluation. The difference between f1 and f2 is that the second is a value, which can be stored in a variable or passed to another function.

Functions which accept other functions as parameters are named high-order functions, for example:

def twice(f: Int => Int): Int => Int = x => f(f(x))

This function...

bookmark search playlist font-size

Change the font size

margin-width

Change margin width

day-mode

Change background colour

Close icon Search
Country selected

Close icon Your notes and bookmarks

Delete Bookmark

Modal Close icon
Are you sure you want to delete it?
Cancel
Yes, Delete