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

Niilo Pirttijärvi
PLUS
Niilo Pirttijärvi
Courses Plus Student 2,354 Points
Posted by 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

Mitch Little
Mitch Little
11,870 Points

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,

Mitch