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Javascript Method Borrowing Example

One can use call keyword to implement method borrowing. Below example shows method borrowing.
var john = {
  name: "John",
  age: 30,
  isAdult: function() {
    console.log(this.name+"'s age is "+this.age);
    if (this.age > 18) {
      return true;
    } else {
      return false;
    }
  }
}

console.log(john.isAdult());

var rita = {
  name: "Rita",
  age: 15
}

console.log(john.isAdult.call(rita));
Observe the last line. How the keyword call is used and how rita object is passed to the function.

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