How can it be that "Function" actually functions as a function?

Question

How can it be that "Function" actually functions as a function?

In JavaScript, there exists a function called "Function". When you create an instance of this function, it returns another function:

var myfunc = new Function('arg1','arg2','return arg1+arg2');

In the above example, the variable myfunc holds a function that adds two given parameters together.

It may seem puzzling that Function is itself a function. After all, how can something be an instance of itself? Additionally, the Object type is also a function and an instance of Function. This creates a loop where Function is an instance of Object, which in turn is an instance of Function. This relationship underscores that functions are objects themselves.

This may appear confusing at first glance, but realizing that functions are objects helps to clarify this seemingly infinite loop.

Thank you!

javascript object

Answer 1

Answer №1

Objects, Functions, and more are all functions - specifically constructor functions.

Just a reminder, creating an object looks like this:

function MyObject() {
    this.foo = 'bar';
}

var my = new MyObject();
alert(my.foo);

By the way, it's not recommended to use new Function(...). A cleaner example would be:

function myfunc(arg1, arg2) { return arg1 + arg2 }

or

var myfunc = function(arg1, arg2) { return arg1 + arg2 };

So, there are limited reasons to utilize new Function() in production code (although template engines might benefit from it).

Answer 2

Objects, Functions, and more are all functions - specifically constructor functions.

Just a reminder, creating an object looks like this:

function MyObject() {
    this.foo = 'bar';
}

var my = new MyObject();
alert(my.foo);

By the way, it's not recommended to use new Function(...). A cleaner example would be:

function myfunc(arg1, arg2) { return arg1 + arg2 }

or

var myfunc = function(arg1, arg2) { return arg1 + arg2 };

So, there are limited reasons to utilize new Function() in production code (although template engines might benefit from it).

Answer 3

Answer №2

The simple explanation is that the structure and relationship between built-in objects like Function, Object, Array, Date, etc., as well as their prototypes, is dictated by the specifications outlined in ECMA-262.

These objects are not constructed in the conventional way; they simply exist within the environment. The connection between them, their prototypes, and their [[Prototype]] is established based on the guidelines set forth in ECMA-262. For example, Function inherits from its own prototype (i.e., Function.prototype === Function[[Prototype]], which then inherits from Object.prototype.

Answer 4

The simple explanation is that the structure and relationship between built-in objects like Function, Object, Array, Date, etc., as well as their prototypes, is dictated by the specifications outlined in ECMA-262.

These objects are not constructed in the conventional way; they simply exist within the environment. The connection between them, their prototypes, and their [[Prototype]] is established based on the guidelines set forth in ECMA-262. For example, Function inherits from its own prototype (i.e., Function.prototype === Function[[Prototype]], which then inherits from Object.prototype.

How can it be that "Function" actually functions as a function?

Answer №1

Answer №2

Similar questions

Is it possible to deactivate the onclick event following a successful ajax request?

Problem encountered when trying to use the sharp package in NuxtJS

jQuery load fails to fill select dropdown

Passing an object in an ajax call to a function: a comprehensive guide

JavaScript code to convert a query into an array

I am experiencing an issue where the jquery sleep function is not being executed during

Install Chakra UI in the latest Next.js project directory

Utilizing typesafe trpc in Node.js to efficiently transfer data between routes

After developing a React application to fetch data from my own API, I encountered the following error message: "TypeError: video.map is not a function". See the code snippet below:

An uncaught SyntaxError occurred due to an omission of a closing parenthesis after the argument list in code that is otherwise

Is Firebug a necessary tool for the functioning of my website?

Creating a carousel of cards using JavaScript, CSS, and HTML

transform array elements into an object

What is the method to dynamically modify the value of location.href using vanilla javascript?

Issue: NextRouter is not mounted when the client is used

Chrome reports a Javascript error: indicating that it is not recognizing the function

Content OverFlow: DropDown Menu is not overlapping the content, but rather pushing it downwards

Tips for defining a relative path in the base URL with AngularJS

Include a clickable hyperlink within a column in JQGrid that, when clicked, triggers a specific Jquery function

Generate the entity and then transfer the data into an array