Writing JavaScript with Only Six Characters

https://javascript.christmas/2019/17

by ewendel • 7 years ago

57 15 7 years ago

javascript.christmas

ewendel2• 7 years ago

I don't write alot of blog posts. Appreciate any feedback you might have :)

getcrunk• 7 years ago

It’s great my guy! Love the recap at the end

Waterluvian• 7 years ago

I love it. But I think it cheats a tiny bit by getting a word that requires only characters from "false". It means you're demonstrating the same trick four times.

Maybe you could do a kind of proof:

1. This is how you get any character 2. This is how you call eval() 3. QED

herohamp• 7 years ago

Yeah the ability to get any character would really show more of how this works

trehalose• 7 years ago

Please run simple code to verify accuracy before publishing it.

The unary plus operator coerces undefined to NaN, not to zero as your article states.

The unary plus operator coerces NaN to NaN, not to zero as your article states. (Remember that NaN is already a number, despite its name.)

If you need to coerce any falsy value to 0, the simplest way is to use bitwise operators. If you want to do it the six character way, I guess use Math.imul

sveingjoby• 7 years ago

Great article. I've seen articles about this concept before, but none of these had such a thorough explanation!

matsemann• 7 years ago

Is there a limit to what one can do with these six characters? Like, now we're reading values from the string "false". We also could read from "true", and maybe undefined (how?). But can one do more? If one can generate "window", one should be able to call functions through window["functionName"]() and do general computing with this, I think?

maury912• 7 years ago

you can obtain undefined by accessing the first element of an empty array. `([])[+!![]]`

ewendel2• 7 years ago

As I understand, there's no limit to what you can do with these six characters.

It quickly gets more complicated though, and will require alot more code:

"undefined": [][![]]+[] (empty array accessed at index 0 turned into string)

"NaN": +{}

"[object Object][object Object]": {}+{}

.. etc

See the full list here:

https://github.com/aemkei/jsfuck/blob/master/jsfuck.js

nchntrz• 7 years ago

Pretty good explanation. For those who want to dive deeper, there is an esoteric language based on these concepts: http://www.jsfuck.com/

maury912• 7 years ago

you can make the final code slightly shorter by obtaining the "e" from "true" instead of "false". `(!![]+[])[+!+[]+!+[]+!+[]]`

74ls00• 7 years ago

World’s most unreadable embedded programming language?

rsiqueira2• 7 years ago

There's Dwitter, a minimalist JavaScript code community, where we use these kind of tricks to write interesting code, demos and concepts with just 140 characters or less: https://dwitter.net/

giancarlostoro• 7 years ago

This is fascinating! Thanks for the share, I had no idea this even existed. Some of the posts are impressive too. Walther is known for their short reset triggers on their handguns for example.

rsiqueira2• 7 years ago

I've just posted a working code on Dwitter based on this "JavaScript with Only Six Characters", it shows 1e+100 turning into Infinity. https://www.dwitter.net/d/16881

Writing JavaScript with Only Six Characters

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