call(), apply(), bind(), new(),

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Wed Mar 23 2022 18:14:19 GMT+0000 (Coordinated Universal Time)

/*
- Implicit Binding
- Explicit Binding
- new Bindidng
- window Binding
*/
//----------------------------------------------
// where is this function invoked?
//----------------------------------------------
// var sayName = function(name) {
//   console.log('Hello, ' + name);
// };

// sayName('Vishnu!');
//----------------------------------------------
// Implicit Binding
// var me = {
//     name: 'Vishnu',
//     age: 25,
//     sayName: function() {
//         console.log(this.name);
//     }
// }

// me.sayName();   // According to implicit binding, `this` keyword is targetting the element left i.e. on the left side of the dot(.), in this case `me`
//----------------------------------------------

// var sayNameMixin = function(obj) {
//     obj.sayName = function() {
//         console.log(this.name);
//     }
// };
// var me = {
//     name: 'Vishnu',
//     age: 25
// };

// var you = {
//     name: 'unknown',
//     age: 21
// };

// sayNameMixin(me);
// sayNameMixin(you);

// me.sayName();
// you.sayName();

//----------------------------------------------

// var Person = function(name, age) {
//     return {
//         name: name,
//         age: age,
//         sayName: function() {
//             console.log(this.name);
//         },
//         mother: {
//             name: 'Mausi',
//             sayName: function() {
//                 console.log(this.name);
//             }
//         }
//     };
// };

// var jim = Person('Jim', 42);
// jim.sayName();
// jim.mother.sayName();

//----------------------------------------------
//----------------------------------------------

// Explicit Binding
// call, apply, bind

// var rand = {
//     name: 'rand',
//     age: 65,
//     // sayName: function() {
//     //     console.log('My name is ' + this.name);
//     // }
// };

// var sayName = function() {
//     console.log('My name is ' + this.name);
// };

// sayName.call(rand);

//----------------------------------------------



// var rand = {
//     name: 'rand',
//     age: 65,
//     // sayName: function() {
//     //     console.log('My name is ' + this.name);
//     // }
// };

// var sayName = function(lang1, lang2, lang3) {
//     console.log('My name is ' + this.name + ' and I know ' + lang1 + ', ' + lang2 + ', ' + lang3);
// };

// var languages = ['JS', 'C++', 'Python'];
// sayName.call(rand, languages[0], languages[1],languages[2]);

// // .apply is a similar thing as .call

// sayName.apply(rand, languages);     // .apply()


//----------------------------------------------


// var rand = {
//     name: 'rand',
//     age: 65,
//     // sayName: function() {
//     //     console.log('My name is ' + this.name);
//     // }
// };

// var sayName = function(lang1, lang2, lang3) {
//     console.log('My name is ' + this.name + ' and I know ' + lang1 + ', ' + lang2 + ', ' + lang3);
// };

// var languages = ['JS', 'C++', 'Python'];
// // sayName.call(rand, languages[0], languages[1],languages[2]);

// // .apply is a similar thing as .call

// // sayName.apply(rand, languages);     // .apply()



// var newFn = sayName.bind(rand, languages[0], languages[1],languages[2]);

// console.log('HERE');
// newFn();


//----------------------------------------------
//----------------------------------------------
//----------------------------------------------
//----------------------------------------------
//----------------------------------------------

// new Binding

// var Animal = function(color, name, type) {
//     this.color = color;
//     this.name = name;
//     this.type = type;
// }

// var Zebra = new Animal('black and white', 'Zorro', 'Zebra');

// console.log(Zebra);

//----------------------------------------------


// window Binding

var sayAge = function() {
    console.log(this.age);
};

var me = {
    age: 25
};

// sayAge.call(me);

sayAge();

window.age = 35;

sayAge();

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call(), apply(), bind(), new(),

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