javascript-handbook

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Object Prototype

• JavaScript prototypes are used to access the properties and methods of objects. To get object prototype we use __proto__or Object.getPrototypeOf()
• __proto__ is next thing up in prototype chain for objects.

  const log = console.log
  let myObj = {};  // same as let myObj = new Object()

  console.dir(myObj.constructor)  // ƒ () { [native code] }

  log(myObj.toString()) //Output ("[object Object]"); the method toString()belongs to the prototype of the object myObj

  log(myObj.__proto__ === myObj.constructor.prototype) // both are pointing to prototype object of constructor

  // accessing constructor's prototype will not work this way 
  log(myObj.constructor.__proto__ ) // not work
  log(Object.getPrototypeOf(myObj.constructor)) // not work
  log(myObj.constructor.prototype) // will work and give root object prototype

  // Also Root-Object.constructor.prototype === Root-Object 

  graph LR;
    myObj.__proto__ --> Root-Object
    myObj.constructor.prototype --> Root-Object
    Object.getPrototypeOf.myObj --> Root-Object
    myObj.__proto__.constructor.prototype --> Root-Object
    Root-Object.constructor.prototype --> Root-Object
    Root-Object --> |Root-Object.__proto__|null