swift 命名空间

import Foundation

class com{
    class upmi{
        
    }
}

import Foundation

extension com.upmi{
    class Say{
        func sayHi()
        {
            print("hi")
        }
    }
    
    

}

import Foundation
extension com.upmi{
    class Do{
        func dosomething()
        {
            print("do some thing")
        }
    }
    
    
    
}

import Foundation


var namespc = com.upmi.Say()
namespc.sayHi()

var namespc2 = com.upmi.Do()
namespc2.dosomething()