Convert an Objective-C method into Swift for NSInputStream (convert bytes into double)

Question

I have the following code in Objective-C:

- (double)readDouble
{
    double value = 0.0;

    if ([self read:(uint8_t *)&value maxLength:8] != 8)
    {
          


        

Answer 1

Here is the updated version for Swift 3 beta 6 which is different, thanx to Martin.

func binarytotype  (_ value: [UInt8], _ : T.Type) -> T
{
    return value.withUnsafeBufferPointer
    {
        UnsafeRawPointer($0.baseAddress!).load(as: T.self)
    }
}

func typetobinary  (_ value: T) -> [UInt8]
{
    var v = value
    let size = MemoryLayout.size
    return withUnsafePointer(to: &v)
    {
        $0.withMemoryRebound(to: UInt8.self, capacity: size)
        {
            Array(UnsafeBufferPointer(start: $0, count: size))
        }
    }    
}

let dd: Double = 1.23456             // -> 1.23456
let d = typetobinary(dd)             // -> [56, 50, 143, 252, 193, 192, 243, 63]
let i = binarytotype(d, Double.self) // -> 1.23456