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0 pointssoperj2y ago0 comments

Are all variables still global unless defined not to be?

0 comments

No, as of eight years ago.

https://en.wikipedia.org/wiki/ECMAScript_version_history#ES2...

I'd rather say yes.

AFAIK core javascript works exactly like 25 years ago, and they haven't changed anything on it, not removing a single keyword or altering a semantics of any less used function, so your 25 years old javascript programs can still run in modern browsers.

soperjOP2y ago

thanks!

bunga-bunga2y ago

Not in a module context:

    # a.mjs
    (()=>{
      a = 1
    })();

    # in a shell
    $ node a.mjs
    ReferenceError: a is not defined

Mystery-Machine2y ago

The short answer is: yes. If you do

And in the .js file: var x = 5. That x is global.

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