Before reading this book, readers need to know about the concepts of object-oriented and imperative programming.

To test the code of this book, you need Docker version 18.06 or higher and Git version 2.18.0 or higher.

You can download the example code files for this book from your account at www.packtpub.com. If you purchased this book elsewhere, you can visit www.packtpub.com/support and register to have the files emailed directly to you.

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2. Select the SUPPORT tab.
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4. Enter the name of the book in the Search box and follow the onscreen instructions.

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We also provide a PDF file that has color images of the screenshots/diagrams used in this book. You can download it here: https://www.packtpub.com/sites/default/files/downloads/MasteringFunctionalProgramming_ColorImages.pdf.

There are a number of text conventions used throughout this book.

CodeInText: Indicates code words in text, database table names, folder names, filenames, file extensions, pathnames, dummy URLs, user input, and Twitter handles. Here is an example: "The instances package contains the implementations of the type classes for basic data types that are present in the language core and the ones defined by the Cats library."

A block of code is set as follows:

public void drink() {
  System.out.println("You have drunk a can of soda.");
}

Any command-line input or output is written as follows:

:help

Bold: Indicates a new term, an important word, or words that you see onscreen. For example, words in menus or dialog boxes appear in the text like this. Here is an example: "The for comprehension is shorthand for sequentially calling flatMap. This technique is called the Monadic flow."