In your opinion, what is the most confusing part of JavaScript?

#discuss

Top comments (14)

Xing Wang • May 16 '19

this

Eugene Karataev • May 17 '19

Type coercion is definitely not obvious in JavaScript

[] == ![] // true 😱

Ken Bellows • May 18 '19

IMHO, don't ever ever ever use == in JavaScript. Always use === instead and forget about type coercion; just explicitly type-cast anything you need to.

Eugene Karataev • May 18 '19

It's a very rare case when you work on a project alone. Other developers can use == and it's necessary to understand how type coercion works.

I agree that most of developers consider == as evil. But Kyle Simpson (You don't know JS author) don't hate type coercion. Moreover, he recomments to use == where necessary.

In other words, coercion, especially implicit coercion, has usages where it actually improves the readability of our code.

Source.

Matt Sparks • May 16 '19

When I started writing JS it was hard to get an understanding of what prototype is and how it's used.

Jonathan Kuhl • May 17 '19

Closures. It's a complicated subject involving an understanding of how the execution context works and how variables are scoped and held within the JavaScript engine. It takes a lot of practice and theory for closures to finally click. It took me like six months to finally grok it.

Laurie • May 16 '19

Javascript has a lot of layers. Understanding what is controlling each piece can be hard to parse if you're new. I actually wrote something on this a while back.