Make an error quine!

Question

Your challenge: write a "program", for a language of your choice, that causes the compiler/interpreter/runtime to produce error output when compiling/running your program which is identical to your program's source code.

Rules:

• Your program may be specific to a particular version or implementation of your language's compiler/interpreter/runtime environment. If so, please specify the particulars.
• Only standard compiler/interpreter/runtime options are permitted. You cannot pass some weird flag to your compiler to get a specific result.
• The program does not need to be syntactically or semantically valid, but I may give a bounty to the best syntactically valid submission.
• The program must not produce any output of its own (e.g. by calling a print or output function). All output generated upon attempting to compile/run the program must originate from the compiler/interpreter/runtime.
• The complete output of the compiler/interpreter/runtime must be exactly identical to your program source code.
• The compiler/interpreter/runtime must generate at least one error message when invoked with your program.

This is a popularity contest. Most creative answer, as determined by upvotes, wins. If you can give a good case for using a standard loophole, you may do so.

Answer 1

m4 (before 1.4.18-3 Termux patch), Termux, Android 11, 35 bytes

Who said the error had to be caused directly?

FORTIFY: %n not allowed on Android

Includes trailing newline.

m4 uses a very old version of Gnulib.

Since Android doesn't support %n in printf, Gnulib will replace every printf function in libc with its own custom implementation.

However, stupidly, said function will still use libc's snprintf function internally (which it is supposedly trying to replace because it doesn't work 🤔), and when using it, it attempts to use %n every single time it is called, even if %n isn't in the original format string.

%n used to be silently ignored on Android (similar to macOS), but Android 11 made these errors fatal, causing this error to be printed followed by abort().

I used set +m to prevent Bash from printing the signal error, and I had to compile from source to undo the -3 patch.

The file itself doesn't matter: m4 is guaranteed to crash no matter what. This includes running with no arguments.

See this Github issue

Answer 2

zsh (Linux)

zsh: command not found: zsh:

Should work with some small changes in just about any other shell.

Answer 3

CoffeeScript

Fails on first error, so it's fairly easy to do:

E:\foo.coffee:1:3: error: unexpected \
E:\foo.coffee:1:3: error: unexpected \
  ^

Demo

E:\>coffee -c foo.coffee
E:\foo.coffee:1:3: error: unexpected \
E:\foo.coffee:1:3: error: unexpected \
  ^

E:\>

Answer 4

Forth

Try it here

This was surprisingly easy to come up with.

a : error(-13): word not found

Answer 5

Bash

$ bash: bash:: command not found
bash: bash:: command not found

Answer 6

ArnoldC, 28 bytes

WHAT THE FUCK DID I DO WRONG

This is the only error message in ArnoldC, though you do have to turn off stack traces.

Answer 7

GNU Make 4.1

make: *** No rule to make target 'No', needed by 'make'.  Stop.

This is syntactically valid:

• Make tries to evaluate the target named make (first target is the default),
• which depends on the target named No,
• which it has no rule for.

Answer 8

Malbolge, 32 bytes

invalid character in source file

Try it online!

Answer 9

Piet, using npiet interpreter

cannot read from `Error.txt'; reason: unknown PPM format

Save as 'Error.txt' and put it in the same folder as the npiet executable. If you want to golf, you can of course choose a shorter filename and adjust the code to match.

Answer 10

Lua

Code:

lua: ERROR.lua:1: function arguments expected near '.'

It seems fairly easy to do with lua. I also modified it to work on ideone.com as:

luac: prog.lua:1: function arguments expected near '.'

Try it.

Answer 11

Rebol

Interestingly, the error message here parses as symbols/tokens:

x
** Script error: x has no value
** Where: do either either either -apply-
** Near: do intern code

So despite looking error-like, it could be made a valid Rebol program if you gave all the words meanings.

However if you wanted an error at the parse phase vs. a runtime error in the code, the program/error could be:

1A
** Syntax error: invalid "integer" -- "1A"
** Where: to case load either either -apply-
** Near: (line 1) 1A

So given that distinction is possible, you can do fun things if you redefine ** from exponentiation into something else (which I can't think of how to make useful for this particular challenge, given it's a quine.)

(Note: Trying to abuse it for a trick uncovered a peculiarity of what happens when ** (an infix operator) is redefined and then used immediately after. I tried:

**: function [:a :b :c :d :e :f] []
** Syntax error: invalid "integer" -- "1A"
** Where: to case load either either -apply-
** Near: (line 1) 1A

My goal was to override the ** so that it would accept its arguments unevaluated. That way ** Syntax error: invalid "integer" -- "1A" (or whatever) would not attempt to assign invalid to error, but pass the symbols to **. But because ** is infix it attempted to raise the function body to the power of Syntax prior to the completion of the assignment of **:.

It can be remedied by putting any token between the [] and the **. But it helps to remember how your language evaluator works. :-P)

Answer 12

R (GUI)

Error: unexpected symbol in "Error: unexpected symbol"

The issue here is replicating the ", which causes the error message to change from unexpected symbol to unexpected string constant. Pretty much any error R throws will have the form Error: <something> in "<bad code>", so you will pretty much always have to contend with the quoting. I tried this several other ways and always ended up falling back here.

Answer 13

Pyth

    s_push: parser stack overflow
Traceback (most recent call last):
  File "pyth.py", line 752, in <module>
    exec(code_to_remove_tools + py_code_line, environment)
MemoryError

Try it online!

Answer 14

Python 3, 28 bytes

SyntaxError: invalid syntax

Answer 15

Javascript (Chrome/V8), 65 41 39 Bytes

Uncaught =u=_=>{throw`=u=${u};u()`};u()

Try it online!

Answer 16

Triangularity, 46 bytes

I smell no triangularity. YOU SHALL NOT PASS!

Try it online!

The language requires programs to be in the form of a triangle. If not, it denies you the gate to programming in the world of triangles. It will not let you pass.

Answer 17

Rust v1.45.2 (via Rust Playground)

Code (1126 bytes):

error: unknown start of token: `
 --> src/lib.rs:1:32
  |
1 | error: unknown start of token: `
  |                                ^
  |
help: Unicode character '`' (Grave Accent) looks like ''' (Single Quote), but it is not
  |
1 | error: unknown start of token: '
  |                                ^

error: unknown start of token: `
 --> src/lib.rs:4:36
  |
4 | 1 | error: unknown start of token: `
  |                                    ^
  |
help: Unicode character '`' (Grave Accent) looks like ''' (Single Quote), but it is not
  |
4 | 1 | error: unknown start of token: '
  |                                    ^

error: character constant must be escaped: '
 --> src/lib.rs:7:56
  |
7 | help: Unicode character '`' (Grave Accent) looks like ''' (Single Quote), but it is not
  |                                                        ^

error: unterminated character literal
 --> src/lib.rs:9:36
  |
9 | 1 | error: unknown start of token: '
  |                                    ^

error: aborting due to 4 previous errors

error: could not compile `playground`.

Try it online (error message might differ in future versions of the language, though)

Compile errors in Rust all start with "error:", so copy/pasting the errors into the source a bunch of times eventually leads to these error messages. Default settings for the Rust Playground were used. That means 2018 edition, stable branch, and debug mode. I don't know what the target triple is.

Answer 18

Vyxal, 42 bytes

slice expected at least 1 arguments, got 0

Try it Online!

Answer 19

Go

Another fairly easy one using the "general approach" provided in the other answer. I still like my JavaScript ones better.

can't load package: package : 
prog.go:1:1: expected 'package', found 'IDENT' can
prog.go:2:2: invalid package name _

Try it.

Answer 20

Lua (console), 35 bytes

This is what you get in the Lua console with the usual iterative approach:

stdin:1: '<name>' expected near '1'

which is a bit shorter than the one obtained for putting the code in a file.

Answer 21

ksh

$ ksh: ksh::  not found.
ksh: ksh::  not found.

Answer 22

Perl

syntax error at quine.pl line 2, at EOF
Execution of quine.pl aborted due to compilation errors.

Replace quine.pl with whatever you named the file and enjoy.

Answer 23

Java, in Eclipse

Syntax error on tokens, delete these tokens

Answer 24

Factor

No word named "No" found in current vocabulary search path

Guess what it prints?

No word named "No" found in current vocabulary search path

Answer 25

Processing IDE

Probably the friendliest error message I've ever seen.

Syntax error, maybe a missing semicolon?

Result

Technically this is cheating a bit because the pane below it prints expected SEMI, found 'error'. Unfortunately the word error is written in single quotes, so trying to copy that into the source of the program causes it to spit out a massive "Badly formed character constant" error... which does not include any singly-quoted words allowing for it to quine itself.

Answer 26

SmileBASIC

NEXT without FOR in 0:1

Whenever the pre-run parser encounters a NEXT which isn't paired with a FOR, it produces the error NEXT without FOR in slot:line. Here, the code is in slot 0 and on line 1.

Answer 27

(t)csh

Unmatched '.

The trailing newline is needed to produce an exact match. Run it with csh quine.csh (or just type it into the shell, that works too).

Answer 28

Cubically, 94 bytes

Notepad: 0

   000
   000
   000
111222333444
111222333444
111222333444
   555
   555
   555

There are newlines at the start and end. (Cubically automatically dumps its memory to STDERR when the program finishes.)

Try it online!

Answer 29

Rust, 323 166 164 bytes

Call your program a. and use rustc a..

error: unknown start of token: \
 --> a.:1:32
  |
1 | error: unknown start of token: \
  |                                ^

error: aborting due to previous error

Answer 30

Pip, 71 bytes

code and error:

R is not a unary operator
Fatal error while parsing, execution aborted.

also:

Hit end of tokens while parsing expression
Fatal error while parsing, execution aborted.

Try it online!