Arrays are collections of values that are stored as a single value. For example, John, Paul, George, and Ringo are names, but arrays let you group them in a single value called The Beatles.
In code, we write this:
let john = "John Lennon" let paul = "Paul McCartney" let george = "George Harrison" let ringo = "Ringo Starr" let beatles = [john, paul, george, ringo]
That last line makes the array: it starts and ends with brackets, with each item in the array separated by a comma.
You can read values from an array by writing a number inside brackets. Array positions count from 0, so if you want to read “Paul McCartney” you would write this:
Be careful: Swift crashes if you read an item that doesn’t exist. For example, trying to read
beatles is a bad idea.
Note: If you’re using type annotations, arrays are written in brackets:
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