Page MenuHomePhorge
Files F7540235

this_demo.cjs
No OneTemporary
Actions

Size
4 KB
Referenced Files
None
Subscribers
None

this_demo.cjs
View Options

// Demonstration of 'this' keyword and 'new' operator
Ant.println("=== Constructor Functions with 'new' and 'this' ===\n");
// Basic constructor function
function Person(name, age) {
this.name = name;
this.age = age;
this.greet = function() {
return "Hello, my name is " + this.name + " and I am " + this.age + " years old.";
};
}
// Create instances using 'new'
Ant.println("Creating person1 with new Person('Alice', 30)");
let person1 = new Person("Alice", 30);
Ant.println("person1.name:", person1.name);
Ant.println("person1.age:", person1.age);
Ant.println("person1.greet():", person1.greet());
Ant.println();
Ant.println("Creating person2 with new Person('Bob', 25)");
let person2 = new Person("Bob", 25);
Ant.println("person2.name:", person2.name);
Ant.println("person2.age:", person2.age);
Ant.println("person2.greet():", person2.greet());
Ant.println();
// Each instance has its own 'this' context
Ant.println("=== Independent 'this' contexts ===");
Ant.println("person1.name:", person1.name);
Ant.println("person2.name:", person2.name);
Ant.println("They are different instances with independent 'this' values");
Ant.println();
// Constructor with methods that use 'this'
function Counter(start) {
this.value = start;
this.increment = function() {
this.value = this.value + 1;
return this.value;
};
this.decrement = function() {
this.value = this.value - 1;
return this.value;
};
this.getValue = function() {
return this.value;
};
}
Ant.println("=== Counter Example ===");
let counter = new Counter(10);
Ant.println("Initial value:", counter.getValue());
Ant.println("After increment:", counter.increment());
Ant.println("After increment:", counter.increment());
Ant.println("After decrement:", counter.decrement());
Ant.println("Final value:", counter.getValue());
Ant.println();
// Multiple counters with independent state
Ant.println("=== Multiple Independent Counters ===");
let counter1 = new Counter(0);
let counter2 = new Counter(100);
Ant.println("counter1 initial:", counter1.getValue());
Ant.println("counter2 initial:", counter2.getValue());
counter1.increment();
counter1.increment();
counter2.decrement();
Ant.println("counter1 after 2 increments:", counter1.getValue());
Ant.println("counter2 after 1 decrement:", counter2.getValue());
Ant.println();
// Constructor with computed properties
function Rectangle(width, height) {
this.width = width;
this.height = height;
this.area = function() {
return this.width * this.height;
};
this.perimeter = function() {
return 2 * (this.width + this.height);
};
}
Ant.println("=== Rectangle Example ===");
let rect1 = new Rectangle(5, 10);
Ant.println("Rectangle 5x10:");
Ant.println(" Width:", rect1.width);
Ant.println(" Height:", rect1.height);
Ant.println(" Area:", rect1.area());
Ant.println(" Perimeter:", rect1.perimeter());
Ant.println();
let rect2 = new Rectangle(3, 7);
Ant.println("Rectangle 3x7:");
Ant.println(" Width:", rect2.width);
Ant.println(" Height:", rect2.height);
Ant.println(" Area:", rect2.area());
Ant.println(" Perimeter:", rect2.perimeter());
Ant.println();
// 'this' refers to the object being constructed
function Car(make, model, year) {
this.make = make;
this.model = model;
this.year = year;
this.displayInfo = function() {
return this.year + " " + this.make + " " + this.model;
};
}
Ant.println("=== Car Example ===");
let car1 = new Car("Toyota", "Camry", 2020);
let car2 = new Car("Honda", "Civic", 2021);
Ant.println("car1:", car1.displayInfo());
Ant.println("car2:", car2.displayInfo());
Ant.println();
// 'this' in nested functions
function Account(owner, balance) {
this.owner = owner;
this.balance = balance;
this.deposit = function(amount) {
this.balance = this.balance + amount;
return this.balance;
};
this.withdraw = function(amount) {
this.balance = this.balance - amount;
return this.balance;
};
this.getInfo = function() {
return this.owner + " has $" + this.balance;
};
}
Ant.println("=== Bank Account Example ===");
let account1 = new Account("Alice", 1000);
Ant.println("Initial:", account1.getInfo());
account1.deposit(500);
Ant.println("After deposit 500:", account1.getInfo());
account1.withdraw(200);
Ant.println("After withdraw 200:", account1.getInfo());
Ant.println();
// Multiple accounts
let account2 = new Account("Bob", 2000);
Ant.println("account1:", account1.getInfo());
Ant.println("account2:", account2.getInfo());
Ant.println();
Ant.println("=== Summary ===");
Ant.println("- 'new' creates a new object");
Ant.println("- 'this' inside constructor refers to the new object");
Ant.println("- Each instance has its own 'this' context");
Ant.println("- Methods can access and modify 'this' properties");

File Metadata

Mime Type
text/plain
Expires
Wed, Jun 17, 1:36 PM (1 d, 22 h)
Storage Engine
blob
Storage Format
Raw Data
Storage Handle
524240
Default Alt Text
this_demo.cjs (4 KB)

Event Timeline