A textual representation of this instance, suitable for debugging.
Calling this property directly is discouraged. Instead, convert an
instance of any type to a string by using the `String(reflecting:)`
initializer. This initializer works with any type, and uses the custom
`debugDescription` property for types that conform to
`CustomDebugStringConvertible`:
struct Point: CustomDebugStringConvertible {
let x: Int, y: Int
var debugDescription: String {
return "(\(x), \(y))"
}
}
let p = Point(x: 21, y: 30)
let s = String(reflecting: p)
print(s)
// Prints "(21, 30)"
The conversion of `p` to a string in the assignment to `s` uses the
`Point` type's `debugDescription` property.
