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Tammy Vo
Tammy Vo

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100 days of SwiftUI - Day 1 & 2

100 days of SwiftUI - Day 1 - Simple Types

100 days of SwiftUI - Day 2 - Simple Types Part 2

Variables:

To create a new variable we need to use "var" to initialize and define.

var operatingSystem = "macOS"
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Strings and Integers:

Swift is type safe.
Strings and Integers can not be mixed.
If there are larger numbers, we can use underscores as thousand separators making it easier to read.

var str = "Hello"
var age = 25
var population = 8_000_000
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Multi-line String:
Start and end with three double quote marks for multi-line strings, this will include line breaks.

var str1 = """
This goes
over multiple
lines
"""

// This way will not show new line breaks in output
var str2 = """
This goes \
over multiple \
lines
"""
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Doubles and booleans:
Doubles will hold a decimal value:

var pi = 3.141
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Booleans will hold a true or false value:

var isCool = true
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String interpolation:
Place any type of variable inside your string by adding a backslash \

var score = 85
var str = "Your score was \(score)"
var results = "The test results are here: \(str)"
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Constants
Use the let keyword to create constants. Constants can be set once and never changed.

let taylor = "swift"
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Type annotations
Swift assigns each variable and constant a type based on what value it’s given when it’s created.

To be explicit about the data type, we can assign it:

let album: String = "Reputation"
let year: Int = 1989
let height: Double = 1.78
let taylorRocks: Bool = true
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Top comments (1)

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vulcanwm profile image
Medea

Woah I don’t know about the underscore in numbers fact!
Nice content!

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