Swift .first()

The .first() method returns the first element of the array that fulfills the specified condition. Otherwise, it returns nil.

Note: .first() is a method while .first is a property. Details about the .first array property can be found near the bottom of this entry.

Syntax

arrayName.first(where: { condition })

The .first() method takes a single condition parameter. It is a closure that returns a boolean value indicating whether a given array element is a match.

Example

var values = [3, 4, 5, 6, 7]

let greaterThanFive = values.first(where: { $0 > 5 })

print(greaterThanFive!) // Force unwrapping optional

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In the example above, the .first() method is searching through the values array. The first item that meets the condition of being greater than 5 will be returned.

This will output:

6

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The .first Property

The .first property returns the first element of the array.

Syntax

arrayName.first

Note: The .first property returns an optional value that should be unwrapped. There are different techniques to unwrap optionals.

Example

var numbers = [5, 1, 8, 4]

print(numbers.first!)

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In the example above, the .first property of the numbers array is printed out. The .first property will return the first item of the numbers array as an optional value. ! forces the expression to unwrap the value of the returned first element.

Note: Force unwrapping optionals in this way is not recommended because it does not handle nil cases.

After unwrapping the value of the returned first element, the output will be:

5

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