1. 1.1.3

    ..<(_:)

    Returns a partial range up to, but not including, its upper bound.

    static func ..< (maximum: Self) -> PartialRangeUpTo<Self>

    Parameters

    maximum

    The upper bound for the range.

    Overview

    Use the prefix half-open range operator (prefix ..<) to create a partial range of any type that conforms to the Comparable protocol. This example creates a PartialRangeUpTo<Double> instance that includes any value less than 5.0.

    let upToFive = ..<5.0
    
    upToFive.contains(3.14)       // true
    upToFive.contains(6.28)       // false
    upToFive.contains(5.0)        // false

    You can use this type of partial range of a collection’s indices to represent the range from the start of the collection up to, but not including, the partial range’s upper bound.

    let numbers = [10, 20, 30, 40, 50, 60, 70]
    print(numbers[..<3])
    // Prints "[10, 20, 30]"