import Foundation

var greeting = "Hello, playground"

let sss = ["1", "2", "3"].map({ "'\($0)'"
}).joined(separator: ",")
print("value in (\(sss))")

let number = NSNumber(7.0)
let number2 = NSNumber(7)



print("number is double: \(number is Double)")
print("number is int: \(number is Int)")
print("number value: \(number)")
print("number type: \(number.objCType)")
          extension NSNumber {
              var type: CFNumberType {
                  return CFNumberGetType(self as CFNumber)
              }
          }

print("number type: \(number.type)")
print("number2 type: \(number2.type)")

let number3 = 7.0

print("number3 is Double: \(number3 is Double)")
print("number3 is Int: \(number3 is Int)")
print("number3 is NSNumber: \(number3 is NSNumber)")