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iOS Enumerations and Optionals in Swift Objects and Optionals Enums with Raw Values

Niilo Pirttijärvi
Niilo Pirttijärvi
Courses Plus Student 2,354 Points

When do I use . and when ()?

I don't fully understand when to use dot notation and when to use braces. Could someone open their usage for me?

1 Answer

Hi Niilo,

Generally there are different cases for dot notation and brackets.

For enums, dot notation can be used to access individual enum cases such as:

enum Compass {
  case south
  case east
  case west
  case north

// assigning Compass case 'south' to direction constant
let direction = Compass.south

The brackets in the case of enums are used to assign associated values to individual enum cases such as:

enum Barcode {
  case upc(Int, Int, Int, Int)
  case qrCode(String)

// using dot notation to access 'upc' case and assigning Integers to its associated value
let barCode = Barcode.upc(1, 2, 3, 4)

Remember to always check out the Swift Language Guide written by Apple. https://developer.apple.com/library/content/documentation/Swift/Conceptual/Swift_Programming_Language/Enumerations.html

I hope this helps. Be sure to let me know if you have any more questions.

All the best,