This document defines various Swift variables and constants, performs printing operations, and demonstrates string interpolation. It also shows how to extend a type to conform to the CustomPlaygroundQuickLookable protocol.

4. let π = 3.14
let ＃ = "minnna_de_swift"
let 📱 = "iPhone 7"
// 使えない文字もある
let ⛩ = "伏見稲荷大社"

7. let `repeat` = 10
print(`repeat`)

8. let maxCapacity = 100
var amount = 10
maxCapacity = 20
amount = 20

10. print("A")
print("A", "B")
print("A", "B", separator: "&")
print("A", "B", separator: "&", terminator: “;")

11. let a = 100
let b = 200
// 文字列の連結
print("a = " + String(a) + ", b = " + String(b))
// 文字列補完構文
print("a = (a), b = (b)”)

12. let value = 10
let string = String(describing: value)

13. String(describing: Int.self) // Int
String(reflecting: Int.self) // Swift.Int
let v = Int.self as Int.Type?
print(v) // "Optional(Swift.Int)n"

14. Mirror(reflecting: value)
for child in Mirror(reflecting: value).children {
print(child)
}

15. extension MyData : CustomPlaygroundQuickLookable {
var customPlaygroundQuickLook: PlaygroundQuickLook {
return .text("My Data")
}
}