Combines a group of related variables and functions into an object.
\nA programming paradigm based on the concept of objects, which can contain data, known as attributes, and code, often known as methods. With the methods of the same instance(objects have a notion of this, which refers to the object itself), we can easily modify the data fields of the object: altering the state of the object.
\nObjects are instances of class. It works like a template which means we can esaily make a new instance of a certain attributes and methods.
\nclass Dog {\n constructor(name, owner) {\n this.name = name\n this.owner = owner\n }\n bark() {\n return 'walf walf'\n }\n\n change_owner(owner) {\n this.owner = owner\n }\n\n let dog1 = new Dog('Bori', 'Rossena')\n dog1.owner // 'Rossena'\n dog1.change_owner('Dayoung');\n dog1.owner // Now Bori's owner is 'Dayoung'\n}Let’s say all dogs have a name and its owner. We can make a new instance of the dog class using new constructor with name and owner parameter. By using the change_owner method, we can also change the state of Bori.
\n1. Encapsulation\n
\nReduce complexity + increase reusability\n
\nUsing OOP, functions end up having fewer parameters, making them easier to use and maintain.
2. Abstraction\n
\nReduce complexity + isolate impact of changes\n
\nAll the complexity is hidden inside. Hiding some of the properties and methods form the outside. It provides simpler interface and reduces the impact of change because we don’t have any that touches these methods outside of the containing objects.
3. Inheritance\n
\nEliminate redundant code\n
\nFor example, when creating HTML elements intead of defining all the properties and methods, we can define them once in a generic object and utilize it.
4. Polymorphism (Many form)\n
\nRefactor ugly conditional statements\n
\nThe way of each HTML element is rendered is different from the others. With OOP, we can implement render method in each of these objects and the render method will behave differently depending on the type of the object we are referencing.
A paradigm that focuses on the computation of pure functions.
\nfunction double(num) {\n return num * 2\n}\n\n// The outcome of double only depends on the input num1. Predictable
\n2. Safe
\n3. Modular
\nFucntional Programming
\n// Create employees array\nlet employees = [\n { name: 'Dayoung', salary: 20000 },\n { name: 'Sehyun', salary: 30000 },\n { name: 'Yohan', salary: 25000 },\n]\n\n// pure function\n// which returns a copy of a single employee with the salary field updated\nlet change_salary = function(employee) {\n return { name: employee.name, salary: employee.salary + 10000 }\n}\n\n// Created a new datatset using the change_salary function\n// map returns a new altered dataset\n// while each alters the state of the object\nlet happier_employees = employees.map(employee => change_salary(employee))\n\nhappier_employees\n// [{name: 'Dayoung', salary: 30000},\n// {name: 'Sehyun', salary: 40000},\n// {name: 'Yohan', salary: 35000}]OOP
\n// Create Employee class\nclass Employee {\n constructor(name, salary) {\n this.name = name\n this.salary = salary\n }\n\n change_salary() {\n this.salary = this.salary + 10000\n }\n}\n\n// Create a instance of employee\nlet employee1 = new Employee('Dayoung', 20000)\nemployee1.salary // 20000\n\n// Use the each method to change salaray attribute of each employee\nemployee1.change_salary()\n\nemployee1.salary // 30000Sources\n
\nhttps://medium.com/@sho.miyata.1/the-object-oriented-programming-vs-functional-programming-debate-in-a-beginner-friendly-nutshell-24fb6f8625cc\nhttps://www.youtube.com/watch?v=pTB0EiLXUC8\nhttps://www.youtube.com/watch?v=FYXpOjwYzcs