1. 1.0.2

    init(_:radix:)

    Creates a new integer value from the given string and radix.

    init?<S>(_ text: S, radix: Int = 10) where S : StringProtocol

    Parameters

    text

    The ASCII representation of a number in the radix passed as radix.

    radix

    The radix, or base, to use for converting text to an integer value. radix must be in the range 2...36. The default is 10.

    Overview

    The string passed as text may begin with a plus or minus sign character (+ or -), followed by one or more numeric digits (0-9) or letters (a-z or A-Z). Parsing of the string is case insensitive.

    let x = Int("123")
    // x == 123
    
    let y = Int("-123", radix: 8)
    // y == -83
    let y = Int("+123", radix: 8)
    // y == +83
    
    let z = Int("07b", radix: 16)
    // z == 123

    If text is in an invalid format or contains characters that are out of bounds for the given radix, or if the value it denotes in the given radix is not representable, the result is nil. For example, the following conversions result in nil:

    Int(" 100")                       // Includes whitespace
    Int("21-50")                      // Invalid format
    Int("ff6600")                     // Characters out of bounds
    Int("zzzzzzzzzzzzz", radix: 36)   // Out of range