Swift version: 5.6
Although it’s generally a good idea to use structs or classes for defining your types, sometimes you’ll find yourself using tuples. If this happens to you, it’s quite tedious having to type the full definition of your tuple whenever you want to use it, so the typealias
lets you create a specific name for it:
typealias Name = (first: String, last: String)
Type aliases are also useful when you might want to change the underlying type used for data. For example, you might store a value as a Float
today, but you want to leave open the option to switch to a Double
later on. In this situation, you’d use typealias
like this:
typealias MyValue = Float
You can then go ahead and use MyValue
everywhere in your code, and if you ever choose to change to Double
you can just change the type alias and all your code will update.
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