Shortest infinite loop producing no output

Question

Your task is to create the shortest infinite loop!

The point of this challenge is to create an infinite loop producing no output, unlike its possible duplicate. The reason to this is because the code might be shorter if no output is given.

Rules

• Each submission must be a full program.
• You must create the shortest infinite loop.
• Even if your program runs out of memory eventually, it is still accepted as long as it is running the whole time from the start to when it runs out of memory. Also when it runs out of memory, it should still not print anything to STDERR.
• The program must take no input (however, reading from a file is allowed), and should not print anything to STDOUT. Output to a file is also forbidden.
• The program must not write anything to STDERR.
• Feel free to use a language (or language version) even if it's newer than this challenge. -Note that there must be an interpreter so the submission can be tested. It is allowed (and even encouraged) to write this interpreter yourself for a previously unimplemented language. :D
• Submissions are scored in bytes, in an appropriate (pre-existing) encoding, usually (but not necessarily) UTF-8. Some languages, like Folders, are a bit tricky to score - if in doubt, please ask on Meta.
• This is not about finding the language with the shortest infinite loop program. This is about finding the shortest infinite loop program in every language. Therefore, I will not accept an answer.
• If your language of choice is a trivial variant of another (potentially more popular) language which already has an answer (think BASIC or SQL dialects, Unix shells or trivial Brainf**k-derivatives like Alphuck), consider adding a note to the existing answer that the same or a very similar solution is also the shortest in the other language.
  
• There should be a website such as Wikipedia, Esolangs, or GitHub for the language. For example, if the language is CJam, then one could link to the site in the header like #[CJam](http://sourceforge.net/p/cjam/wiki/Home/), X bytes.
• Standard loopholes are not allowed.

(I have taken some of these rules from Martin Büttner's "Hello World" challenge)

Please feel free to post in the comments to tell me how this challenge could be improved.

Catalogue

This is a Stack Snippet which generates both an alphabetical catalogue of the used languages, and an overall leaderboard. To make sure your answer shows up, please start it with this Markdown header:

# Language name, X bytes

Obviously replacing Language name and X bytes with the proper items. If you want to link to the languages' website, use this template, as posted above:

#[Language name](http://link.to/the/language), X bytes

Now, finally, here's the snippet: (Try pressing "Full page" for a better view.)

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body{text-align:left!important}#answer-list{padding:10px;width:500px;float:left}#language-list{padding:10px;padding-right:40px;width:500px;float:left}table thead{font-weight:700}table td{padding:5px}

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script> <link rel="stylesheet" type="text/css" href="//cdn.sstatic.net/codegolf/all.css?v=83c949450c8b"> <div id="language-list"> <h2>Shortest Solution by Language</h2> <table class="language-list"> <thead> <tr><td>Language</td><td>User</td><td>Score</td></tr> </thead> <tbody id="languages"> </tbody> </table> </div> <div id="answer-list"> <h2>Leaderboard</h2> <table class="answer-list"> <thead> <tr><td></td><td>Author</td><td>Language</td><td>Size</td></tr> </thead> <tbody id="answers"> </tbody> </table> </div> <table style="display: none"> <tbody id="answer-template"> <tr><td>{{PLACE}}</td><td>{{NAME}}</td><td>{{LANGUAGE}}</td><td>{{SIZE}}</td><td><a href="{{LINK}}">Link</a></td></tr> </tbody> </table> <table style="display: none"> <tbody id="language-template"> <tr><td>{{LANGUAGE}}</td><td>{{NAME}}</td><td>{{SIZE}}</td><td><a href="{{LINK}}">Link</a></td></tr> </tbody> </table>

Answer 1

ACIDIC, 1 byte

A single newline character. In the C# interpreter, the empty program (i.e., the second line) just loops forever.

Answer 2

Ceylon, 30 29 bytes

This is an eternal loop (which also will not run out of memory or stack or something), 30 bytes:

shared void l(){while(true){}}

This can be golfed down one more byte to 29:

shared void l(){while(1<2){}}

In the Ceylon web runner you have to remove the function wrapper, getting this 12 byte snipped:

while(1<2){}

(I had to kill my Chromium window when trying this.)

This eternal recursion will quickly run out of stack space (about 1024 calls on my JVM implementation, with a StackOverflowError), 22 bytes:

shared void r() {r();}

I wouldn't consider this a valid solution.

Note that the for-loop (which is the shortest endless loop in Java) in Ceylon can only loop over an iterable, and all ways of constructing an infinite iterable are longer. Here is one example (38 bytes):

shared void f(){for(x in{1}.cycled){}}

Answer 3

BSM, 1 byte

A single space character. Had to use some brute-forcing for this... After about 125 cycles, it loops between the states 55, EF, B1, 5A, AD, B2, D9, DC, 9C, 13, 19, and F9.

Answer 4

Enigma-2D, 2 bytes

RL

The IP alternates between moving rightwards and leftwards.

Answer 5

MarioLANG(4 Bytes)

><
==

Answer 6

Nim, 16 bytes

while on:discard

on is an alias for true. Nim disallows expressions that aren't explicitly discarded, so we just discard nothing.

Answer 7

Logicode, 24 bytes

circ r(a)->r(a)
out r(1)

Logicode is a new language that I made recently. It only consists of the basic logic gates AND, OR and NOT.

It also contains some nifty stuff like conditionals, make-your-own circuits, and output.

Basically, the first line declares a new circuit, r, with an argument a, and declares the output of the circuit to be r(a). This basically results in an infinite loop.

out r(1) outputs r(1).

Answer 8

Ru, 4 bytes

¿Ϟ{}

¿ call a function while koppa is not 0/nil/false. But since Ϟ also return its argument, it's possible to chain ¿ and Ϟ.

Answer 9

Racket 18 bytes

(λ()(let g()(g)))

Answer 10

Emotinomicon, (2 chars) 6 bytes

ℹ⏩

I cleverly chose the ℹ character for 3 bytes instead of 4. Explanation:

ℹ⏩ explanation
ℹ  push the imaginary unit to the stack
 ⏩ close loop

It works, because 1) ⏩ has got a value (i) 2) ⏩ can't find a ⏪.

To test the code, do the following:

1. Open the interpreter.
2. Clean the box and then put a 😷 in it (not part of the code, just in case you have a dirty output stream).
3. Paste the code after that one-big-toothed strange guy.
4. Click on "generate explanation". Watch the steps done there (also, no mono-spacing issues).
5. Click on "submit". Warning: the code will run after this step!

Answer 11

D2, 3 bytes

+[]

Same as Brainfuck

More interesting version using the preprocessor (the code is actually never executed because the infinite loop is in the preprocessor):

(@a)a@a

Simple recursive macro

Answer 12

Lithp, 40 bytes

((platform ext)(invoke (stdin) resume))

There are presently no loop constructs in my language. Instead, we tell NodeJS (in which Lithp is implemented) to resume the process.stdin stream. We haven't setup a handler, but the process will never exit.

In fact, you have to send a kill message to abort the application.

Answer 13

PHP, 9 bytes

back to basic:

L:goto L;

^_^

Answer 14

Clojure, 21 10 bytes

(#(recur))

After posting a question of meta regarding what's considered a full program in Clojure, it seems that the above is acceptable. If you paste it in an empty source file, it will run.

Answer 15

TI-83 Hex Assembly, 3 bytes

PROGRAM:L
:AsmPrgm
:C3959D

Run it with Asm(prgmL). Jumps to itself over and over. The only way to stop the program is to physically remove the batteries from the calculator. I count each pair of hex digits as one byte.

Answer 16

Pushy, 2 1 bytes

[

Try it online!

Hah, [ is just an infinite loop, that's its only function if you see here.

Answer 17

FALSE, 6 bytes

[1][]#

This is a while loop (#) with an empty body function ([]) and a condition function that always yields a truthy value. It runs forever without yielding output.

Interpreter used.

Answer 18

Lithp, 27 bytes

 ((def x #::((next x)))(x))

Define a function, x, which uses tail recursion (via next) to call itself. Then call function x.

This program will never finish. You can't even CTRL+C out of it since keyboard input isn't handled in Node.js whilst in a while loop.

If one were to provide the -d flag to run.js, they would see the function calling itself over and over, never finishing nor running out of stack space.

This was a neat feature to get working in my language. Typically one would use some sort of logic flow to determine whether to return a value or tail recurse back into the current function (using next or recurse.)

The implementation of such tail recursion was fairly simple, but its implications in my functional language are great. My feature set is getting nearer and nearer to Erlang's every week. And that's fun.

Answer 19

uBASIC, 7 bytes

1GOTO1

Note trailing newline. Trivial BASIC variant.

Try it online!

Answer 20

Excel VBA, 7 Bytes

Do:Loop

Note: the above freezes Excel - the shortest Excel VBA loop that does not do this is Do:DoEvents:Loop (16 Bytes)

Answer 21

GNU Sed, 3 bytes

Unlike this answer by @Digital Trauma (which relies on bug #21250: sed: empty label for :/b/t commands), does only use documented Sed commands, in the same byte count.

Golfed

G 
D

Explained

G       #Append a newline to the contents of the pattern 
        #space, and then append the contents of the hold
        #space to that of the pattern space.

D       #Delete text in the pattern space up to the 
        #first newline, and restart cycle with the 
        #resultant pattern space, without reading a new 
        #line of input.

Answer 22

tcl, 7 bytes

vwait v

Explanation

Answer 23

Forte, 4 bytes

1REM

Without an END statement, Forte programs loop infinitely. The empty program is an error, so we leave a comment.

Try it online!

Answer 24

OIL, 1 byte

6

TIO does not currently support OIL.

Explanation:

6 // Jump to cell A.
0 // Implicit 0.

Answer 25

Samau, 3 bytes

`xx

Explanation

`x      push the quoted function [x]
  x     execute it without popping it 

It works like the Mathematica program #0[]&[], but Samau doesn't have an iteration limit.

Answer 26

Lua and RBX.Lua, 14 bytes

while 1 do end

Pretty self explanatory. While 1 is true, it will iterate through the loop.

Answer 27

Decimal, 6 bytes

91D91D

Pretty simple:

91D   ; declare jump 1
91D   ; goto jump 1

Try it online! I mean, not exactly try it, but... you know what I mean.

Answer 28

Fission 2, 1 byte

R

Try it online!

Spawns an atom moving right, wraps on the end of the line, R simply sets the atom's direction to right after the program has started

Answer 29

XSLT, 173 bytes

<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0"><xsl:template name="a" match="/"><xsl:call-template name="a"/></xsl:template></xsl:stylesheet>

Requires a trivial XML file as input (<root /> will suffice), since XSLT won't actually do anything unless given input. You can test it here. It's possible to remove some of the spaces or the xmlns:xsl attribute and still have it parse, but most XSLT lint programs will reject the shorter versions, so this is the shortest "correct" XSLT script I could come up with that loops forever.

Answer 30

Lean Mean Bean Machine, 3 bytes

O
~

Marble spawns at O, drops to ~, which teleports it back up to the top of the column.