Ejercicios

1. ¿Cual es la salida?

   > String.prototype.repeat = function(times) {
   ...   return new Array(times+1).join(this)
   ... }
   [Function]
   >  
   undefined
   > "hello".repeat(3)
   
   >
   

2. ¿Cuales son los resultados?

   > z = Object.create({x:1, y:2})
   {}
   > z.x
   
   > z.y
   
   > z.__proto__
   
   > z.__proto__.__proto__
   
   > z.__proto__.__proto__.__proto__
   

3. Describa las salidas:

   > obj = {x : 'something' }
   { x: 'something' }
   > w = Object.create(obj)
   {}
   > w.x
   'something'
   > w.x = "another thing"
   'another thing'
   > w.__proto__
   
   > obj == w.__proto__
   

4. Explique la salida:

   > obj = {x : { y : 1} }
   { x: { y: 1 } }
   > w = Object.create(obj)
   {}
   > w.x == obj.x
   true
   > w.x.y = 2
   2
   > obj
   { x: { y: 2 } }
   >
   

5. Explique las salidas:

   > inherit = Object.create
   [Function: create]
   > o = {}
   {}
   > o.x = 1
   1
   > p = inherit(o)
   {}
   > p.x
   1
   > p.y = 2
   2
   > p
   { y: 2 }
   > o
   { x: 1 }
   > o.y
   undefined
   > q = inherit(p)
   {}
   > q.z = 3
   3
   > q
   { z: 3 }
   > s = q.toString()
   '[object Object]'
   > q.x+q.y+q.z
   6
   > o.x
   1
   > o.x = 4
   4
   > p.x
   4
   > q.x
   4
   > q.x = 5
   5
   > p.x
   4
   > o.x
   4