MasonHolland / swift-5-essential-training

swift-5-essential-training

Compiled programming language that works with preexisting Objective-C modules and frameworks.

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Variables and Constants

• The var keyword declares a variable that can be changed at any time.
• The let keyword declares a variable as a constant, which cannot be changed after it's value is assigned
• camelCase is encouraged for Swift
• No line ending symbol

var currentHealth = 90
let maxHealth = 100

currentHealth = 13

var inventoryItems = 5, equipmentSlots = 3, currentGold = 42

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Type Safety and Inference

Swift is a type safe language, meaning that every variable needs to have a specific type and a value that matches. Swift can also infer a variables type from it's assigned value, making variable declarations more concise.

// Type inference
var currentHealth = 90

// Type annotation
var characterName: String
characterName = "Guts"

// Type annotation and Inference
var maxHealth: Int = 100

// Multiple variables - type annotation shorthand
var inventoryItems, equipmentSlots, currentGold: Int

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Logging and Commenting

Commenting your code is the first step to keeping it clean and organized., and the print statement is your best friend when it comes to testing that your code is working as expected.

Single line comment = //

Multi line comment = /* */

String Interpolation

print("Hello \(2+3) World")

Anything between the characters \() will be interpolated into a string.