How to access a Swift enum associated value outside of a switch statement

As others have pointed out, this is now kind of possible in Swift 2:

import CoreGraphics

enum Line {
    case    Horizontal(CGFloat)
    case    Vertical(CGFloat)
}

let min = Line.Horizontal(0.0)
let mid = Line.Horizontal(0.5)
let max = Line.Horizontal(1.0)

func doToLine(line: Line) -> CGFloat? {
    if case .Horizontal(let value) = line {
        return value
    }
    return .None
}

doToLine(min) // prints 0
doToLine(mid) // prints 0.5
doToLine(max) // prints 1