A few JavaScript quines

quine-examples.js

// Today, I noticed that someone favorited this tweet of mine from 2012:
// https://twitter.com/cowboy/status/232587756486938624
// !function $(){console.log('!'+$+'()')}() #quine

// So I fooled around for a little bit:

// Shortest JavaScript quine?
(function _(){return'('+_+')()'})()

// Have fun with this one!
(function $($_$,_,_$,_$_,$_){return[_=_[$_$](_$[$_++])][_[$_++]][_[$_++]]([][_[$_--]][_[$_++]](_$_,function($$){return _$[$$]||[$_,_$_,_,$_$,$][$_--]},$_++),_[++$_])})('split',',join,call,map',',()\'\\','1821383038303012434430383082',0)

quine-test.js

// Test a quine like so:
a= your_quine_code
a===eval(a) // must be true

// Eg.
a= (function _(){return'('+_+')()'})()
a===eval(a) // true

Here's mine, it passes the test:
undefined

@geoffswift lol come on, if that counts the shortest answer is just:

1

Here's one that works when saved to quine.js and run with node quine.js:

s = "; console.log('s =', JSON.stringify(s), s)" ; console.log('s =', JSON.stringify(s), s)

okay here's my shortest quine:

yes. That's it.
...
okay, if you want a real one here it is:
function q(){return q+";q()"};q()
there.
magic.

@phi548183 A quine cannot read its own source code

Some idea.
Both are same in code

(_=$=>`(_=${_})()`)()
(l=i=>`(l=${l})()`)()

But not in text

out by using console.log:
q="'";s='q="";s=;f=s.substr.bind(s);console.log(f(0,3)+q+f(3,4)+q+s+q+f(7));';f=s.substr.bind(s);console.log(f(0,3)+q+f(3,4)+q+s+q+f(7));

const f = () => {
  console.log("const f =", f.toString(), "; f();");
} ; f();

(()=>{var arr=["(()=>{var arr=",0,";arr[1]=JSON.stringify(arr);return arr.join(\"\");})()"];arr[1]=JSON.stringify(arr);return arr.join("");})()

a='r=(s,p,q)=>s.replaceAll(p,q);b="\'"+r(r(a,"\\\\","\\\\\\\\"),"\\\'","\\\\\'")+"\'";console.log("a="+b+";"+a);';r=(s,p,q)=>s.replaceAll(p,q);b="'"+r(r(a,"\\","\\\\"),"\'","\\'")+"'";console.log("a="+b+";"+a);

My current favorite is this because it's both the shortest and also has a lot of $$$ bling

($=()=>`($=${$})()`)()

[edit: not the shortest, see below]

$=_=>`$=${$};$()`;$()

Nice! It seems like these two would be tied for shortest, but I think CodingInvoker's wins with a 50% higher bling-per-character ratio

($=_=>`($=${$})()`)()
$=_=>`$=${$};$()`;$()

ok
(function q(){return q;})

Here`s mine:

Here`s mine:

can you explain that in greater detail?
I love the example but i am just curious how you got this.

well, if you run it it prints out its own sourcecode. valid in every language.
a cheap trick within the quine rules.

First of all, mine is:

(_=$=>`(_=${_})()`)()

But I prefer:

Uncaught SyntaxError: Unexpected identifier

Uncaught SyntaxError: Unexpected identifier

excellent

Actually, these quines aren't real quines because they read themselves. Here's my take:

const charCode = 34;
const code = [
    "const charCode = 34;",
    "const code = [",
    "",
    "];",
    "for (let i = 0; i < 2; i++) console.log(code[i])",
    "for (let i = 0; i < code.length; i++) console.log(code[2] + '    ' + String.fromCharCode(charCode) + code[i] + String.fromCharCode(charCode) + ',');",
    "for (let i = 3; i < code.length; i++) console.log(code[i])"
];

for (let i = 0; i < 2; i++) console.log(code[i]);
for (let i = 0; i < code.length; i++) console.log(code[2] + '    ' + String.fromCharCode(charCode) + code[i] + String.fromCharCode(charCode) + ',');
for (let i = 3; i < code.length; i++) console.log(code[i])

repl

Of course it could be a lot shorter but I just wanted to show that we could add any amount of code and the quine would work with a few tweaks

I made one that creates a string with code to log itself plus the parts around it then evaluates it
a="console.log('a='+String.fromCharCode(34)+a+String.fromCharCode(34)+';eval(a)')";eval(a)

Does this count?
(() => { !function () { console.log((${arguments.callee.caller.toString()})()) }() })()

I'VE DONE IT!
I created THE SMALLEST quine, it passes the quine test above and technically is one depending on how you define it.
It also should work in most programming languages!
You're never going to believe how amazing the code is:
0
Yep, that's it. Just the number 0. When run it prints 0, which is the code. It passes the test: 0===eval(0) making it the smallest quine (although not a very interesting one)

@rubyswolf
It's not a Quine, someone already proposed this idea in this thread, and even if it does, the empty program results with an empty output so `` is the smallest Quine.

oh I missed that one oops @donno2048

without equality sign and function keyword

 ({0(){alert(`({${this[0]}})[0]()`)}})[0]()

// Never ending eval...
let x ="let x =%22quinner%22;let y=decodeURI(x).replace(/quinner/, x);alert(y);eval(y);";let y=decodeURI(x).replace(/quinner/, x);alert(y);eval(y);

// Never ending eval...
let x ="let x =%22quinner%22;let y=decodeURI(x).replace(/quinner/, x);alert(y);eval(y);";let y=decodeURI(x).replace(/quinner/, x);alert(y);eval(y);

A quine in programming is a self-replicating code that, when executed, produces retro bowl its own source code as the output.