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

Identifying and capturing changes in child scope events or properties in Angular

Click on the print icon in the modal window

Access to PHP script (IF) unattainable following a POST occurrence

Guide to configuring Javascript as a Blade template for integration into an API endpoint

I have a website hosted on Heroku and I am looking to add a blog feature to it. I initially experimented with Butter CMS, but I found it to be too pricey for my budget. Any suggestions on

What is the best way to create fading text effects in an AngularJS application?

comparing caching with jquery deferred against promise

Troubleshooting: Issues with Custom Image Loader in Next.js Export

Automatically load VueJS components based on the prefix of the tag

The callback response in Node's exec function is behaving incorrectly

What is the best way to embed two controllers within an AngularJS webpage?

How can I determine the remaining amount of scroll left in my HTML document?

Issues arise when the Angular controller fails to load

Alert: The flattening operation is not a recognized function. Proceed with --force option to proceed

Create a function that triggers a fade-out effect on one button when another button is clicked

Using Javascript's OnChange event to dynamically update data

Tips for incorporating a CSS transition when closing a details tag:

What is the best way to accomplish a smooth transition of background colors similar to this design

Is Angular Translate susceptible to race conditions when using static files for multi-language support?

The color scheme detection feature for matching media is malfunctioning on Safari