Swift相当于Objective-C FourCharCode单引号文字(例如’TEXT’)

我正在尝试在 Swift中复制一些Objective C cocoa.一切都很好,直到我遇到以下情况：

// Set a new type and creator:
unsigned long type = 'TEXT';
unsigned long creator = 'pdos';

如何从这样的单引号字符文字创建Int64(或正确的Swift等价物)？

类型：

public typealias AEKeyword = FourCharCode
public typealias OSType = FourCharCode
public typealias FourCharCode = UInt32

我在我的Cocoa Scripting应用程序中使用它,它认为字符> 0x80正确

func OSTypeFrom(string : String) -> UInt {
  var result : UInt = 0
  if let data = string.dataUsingEncoding(NSMacOSRomanStringEncoding) {
    let bytes = UnsafePointer<UInt8>(data.bytes)
    for i in 0..<data.length {
      result = result << 8 + UInt(bytes[i])
    }
  }
  return result
}

编辑：

另外

func fourCharCodeFrom(string : String) -> FourCharCode
{
  assert(string.count == 4,"String length must be 4")
  var result : FourCharCode = 0
  for char in string.utf16 {
    result = (result << 8) + FourCharCode(char)
  }
  return result
}

或者仍然很快

func fourCharCode(from string : String) -> FourCharCode
{
  return string.utf16.reduce(0,{$0 << 8 + FourCharCode($1)})
}