This is how to create a function in Swift. Lately, I've been able to write without even looking at online articles.
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| import UIKit | |
| // 横幅と縦幅から面積を計算 | |
| func area(height: Double, width: Double) -> Double { | |
| return height * width | |
| } | |
| // 引数名と関数の中での変数名が異なる | |
| func area2(height h: Double, width w: Double) -> Double { | |
| return h * w | |
| } | |
| // 引数名を省略 | |
| func area3(_ h: Double, _ w: Double) -> Double { | |
| return h * w | |
| } | |
| // 面積を求める | |
| print(area(height: 3.00, width: 3.00)) | |
| print(area2(height: 3.00, width: 3.00)) | |
| print(area3(3.00, 2.00)) | |
| // 参照渡し | |
| func double(_ x: inout Int) { | |
| x = x * 2 | |
| } | |
| var x = 100 | |
| var y = 0 | |
| print("x = \(x)") | |
| // x = 100 | |
| double(&x) | |
| print("x = \(x)") | |
| // x = 200 |