Conventions

In this book, you will find a number of text styles that distinguish between different kinds of information. Here are some examples of these styles and an explanation of their meaning.

Code words in text, database table names, folder names, filenames, file extensions, pathnames, dummy URLs, user input, and Twitter handles are shown as follows: "In Swift, you use var for variables, and let for constants."

A block of code is set as follows:

var count = 5
var msg : String
var total : Double = 0

When we wish to draw your attention to a particular part of a code block, the relevant lines or items are set in bold:

Protocol <protocol1, protocol2,…>

New terms and important words are shown in bold. Words that you see on the screen, for example, in menus or dialog boxes, appear in the text like this: "Xcode helps you with this by providing the history button in the results sidebar, on the line of the number of times."