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Swift Programming: The Big Nerd Ranch Guide
book

Swift Programming: The Big Nerd Ranch Guide

by Matthew Mathias, John Gallagher
December 2015
Intermediate to advanced
400 pages
13h 3m
English
Big Nerd Ranch Guides
Content preview from Swift Programming: The Big Nerd Ranch Guide

Translating a Dictionary to an Array

Sometimes it is helpful to pull information out of a dictionary and put it into an array. Suppose, for example, that you want to list all of the movies that have been rated (without their ratings).

In this case, it makes sense to create an instance of the Array type with the keys from your dictionary.

Listing 10.12  Sending keys to an array

import Cocoa var movieRatings = ["Donnie Darko": 4, "Chungking Express": 5, "Dark City": 4] print("I have rated \(movieRatings.count) movies.") let darkoRating = movieRatings["Donnie Darko"] movieRatings["Dark City"] = 5 movieRatings let oldRating: Int? = movieRatings.updateValue(5, forKey: "Donnie Darko") if let lastRating = oldRating { print(lastRating) ...
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Swift Programming: The Big Nerd Ranch Guide

Swift Programming: The Big Nerd Ranch Guide

Matthew Mathias, John Gallagher

Publisher Resources

ISBN: 9780134398068Purchase book