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var <varname> = - the classic.
let <varname> = - the modern.
const <varname> = - the unchanging
<varname> = - the 'oops I made this global by not actually using one'
window.<varname> = - the 'deliberate' global

At a guess, anyway... Been wracking my brains to back when I started with classic ASP and early JS in the likes of IE 6 and such, and this is all I can remember... but the brain's not what it used to be, so probably wrong :D


For clarification, <varname> = throws an error in 'strict mode' which means you can't use them inside type="module" scripts, as they are in strict mode by default (source:


Definitely - and that's one reason using 'strict' is a massively good thing to do :D Or, perhaps better, use TypeScript and benefit from a more deliberate variable declaration syntax.


Very nice, can you guess the bonus and deprecated variable from js 1.8?


Nope :D I never followed the language definition that far back, I have to admit - and Googling the MDN releases isn't very helpful.

It's a shortcut for creating linked lists? I can see why it got deprecated. Looks like it was a mozilla only tooling...

I have no idea, I didn't stick around to find out. 😂


var is not an assignment keyword. If anything, it is a declaration keyword. If you want another way to declare a global variable (in a browser) simply add an id to a DOM node.


I'm not sure I follow, can you elaborate on why var is not a means to assign a variable to a space in memory.

Also not sure how a html attributes is a variable unless it has some special relationship that other attributes do not?

Happy to learn new things, not trying to be annoying.


Does 'this.value = value' count as keyword variable assignment?

Classic DEV Post from Jan 19 '19

Learning data visualization

List of resources to learn data visualization

Adam Crockett profile image
I work at ForgeRock as a Front End Engineer, I play with all sorts really. Lately WASM is my toy of interest.