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

Ed (1 byte)

All the other solutions thus far are long and ugly. I suppose that is because of the nature of most error messages. But a good error message is elegant in its simplicity. For that, look no further than ed.

?

Save this to a file called edscript and run with ed < edscript, or run ed<<<?. The result:

?

The question mark is written to stderr and ed returns 1, so this actually is an error message. I wonder why ed isn't very popular?

False (0 bytes)

Run with false filename. It writes the program's source code (i.e. nothing) to stderr and returns 1. Of course, calling false a programming language is questionable, and the zero byte quine is unoriginal, but I thought I might as well add it. There is probably some interpreter for a language that prints no error messages, and could replace false.

Now I wish this was code golf.

Answer 2

Windows Command Prompt

& was unexpected at this time.

Answer 3

CoffeeScript, syntactically valid

As tested on their website using Chrome or Firefox.

ReferenceError: defined is not defined

You can replace defined with anything that's not a built-in variable, but I thought this version was fun. Unfortunately, undefined is not defined in particular doesn't work as a quine.

In CoffeeScript this isn't even a syntax error, because it compiles. This is technically a runtime error in JavaScript, albeit a boring one. CoffeeScript is a likely candidate to produce some more interesting runtime error quines because a lot of funny sentences are valid code. E.g. the above example compiles to

({
  ReferenceError: defined === !defined
});

Answer 4

Python

Spyder

Well, a rather trivial solution for the Spyder IDE is to raise a SyntaxError.

Code and identical output:

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/Applications/Spyder.app/Contents/Resources/lib/python2.7/spyderlib/widgets/externalshell/sitecustomize.py", line 540, in runfile
    execfile(filename, namespace)
  File "/Users/falko/golf.py", line 1
    Traceback (most recent call last):
                         ^
SyntaxError: invalid syntax

(Python 2.7.8 with Spyder 2.2.5)

---

Terminal

An alternative solution for Python started from command line struggles with an unexpected indent.

Command:

python golf.py

Code and identical output:

  File "golf.py", line 1
    File "golf.py", line 1
    ^
IndentationError: unexpected indent

---

ideone.com

On ideone.com a solution might be as follows. (Try it!)

Code and identical output:

Traceback (most recent call last):

  File "<string>", line 1, in <module>
  File "/usr/lib/python2.7/py_compile.py", line 117, in compile
    raise py_exc
py_compile.PyCompileError: SyntaxError: ('invalid syntax', ('prog.py', 1, 22, 'Traceback (most recent call last):\n'))

(This is for Python 2. An example for Python 3 is trivial but with 15 lines of "code" rather lengthy.)

---

General approach:

How to create your own solution in 2 minutes?

1. Open a new file in an IDE of your choice.
2. Bang your head onto the keyboard in front of you.
3. Compile.
4. Replace the code with the compiler error message.
5. Repeat steps 3 and 4 until the code converges.

I bet such a procedure terminates pretty quickly in most cases!

Answer 5

Windows .EXE, 248 bytes

The version of this file is not compatible with the version of Windows you're running. Check your computer's system information to see whether you need an x86 (32-bit) or x64 (64-bit) version of the program, and then contact the software publisher.

No, really. Save as quine.txt, then rename to quine.exe (or download it here):

Answer 6

><> - 25 Bytes

something smells fishy...

In Fish, any bad instruction outputs the error: "something smells fishy...". Since s is not a valid command, it errors immediately.

Answer 7

Whitespace

First I thought this is clearly impossible. But actually it is trivial as well. -.-

Fail: Input.hs:108: Non-exhaustive patterns in function parseNum'

Try it.

Yeah, my first whitespace program! ;)

Answer 8

Chicken

Error on line 1: expected 'chicken'

Answer 9

JavaScript

Since different browsers use different JavaScript compilers, they produce different messages. These are, however, rather trivial solutions.

V8 (Chrome 36 / Node.js)

SyntaxError: Unexpected identifier

SpiderMonkey (Firefox 31)

SyntaxError: missing ; before statement

Chakra (Internet Explorer 11)

Expected ';'

Answer 10

Commodore 64 Basic

?SYNTAX  ERROR

When run on the emulator of your choice (or an actual Commodore 64), produces

?SYNTAX  ERROR

This is, in fact, a syntactically-valid one-line program. The question mark is a shortcut for PRINT, and SYNTAX and ERROR are valid variable names. The error occurs because the parser gets confused by the substring OR in ERROR.

Answer 11

Microsoft Excel

Formula: #DIV/0!

Error Message: #DIV/0!

In order to enter a formula without using an equals sign, go into Excel Options/Advanced/Lotus Compatibility Settings and enable Transition Formula Entry.

Answer 12

Bash (32)

Save as file named x:

x: line 1: x:: command not found

When run:

>> bash x
x: line 1: x:: command not found

Answer 13

Java 8 compilation error quine (12203 bytes)

Generated on windows + mingw with java 1.8.0_11 jdk, using this command:

echo a > Q.java; while true; do javac Q.java 2> Q.err; if [ $(diff Q.err Q.java | wc -c) -eq 0 ]; then break; fi; cat Q.err > Q.java; done

May not be the shortest one, may not be the longest one either, more a proof of concept. Works because error output shows at most 100 errors.

Q.java:1: error: class, interface, or enum expected
Q.java:1: error: class, interface, or enum expected
^
Q.java:1: error: <identifier> expected
Q.java:1: error: class, interface, or enum expected
                      ^
Q.java:1: error: <identifier> expected
Q.java:1: error: class, interface, or enum expected
                                 ^
Q.java:1: error: as of release 5, 'enum' is a keyword, and may not be used as an identifier
Q.java:1: error: class, interface, or enum expected
                                      ^
  (use -source 1.4 or lower to use 'enum' as an identifier)
Q.java:1: error: = expected
Q.java:1: error: class, interface, or enum expected
                                           ^
Q.java:2: error: <identifier> expected
Q.java:1: error: class, interface, or enum expected
      ^
Q.java:2: error: ';' expected
Q.java:1: error: class, interface, or enum expected
       ^
Q.java:2: error: illegal start of type
Q.java:1: error: class, interface, or enum expected
        ^
Q.java:2: error: = expected
Q.java:1: error: class, interface, or enum expected
               ^
Q.java:2: error: <identifier> expected
Q.java:1: error: class, interface, or enum expected
                      ^
Q.java:2: error: <identifier> expected
Q.java:1: error: class, interface, or enum expected
                                 ^
Q.java:2: error: as of release 5, 'enum' is a keyword, and may not be used as an identifier
Q.java:1: error: class, interface, or enum expected
                                      ^
  (use -source 1.4 or lower to use 'enum' as an identifier)
Q.java:2: error: = expected
Q.java:1: error: class, interface, or enum expected
                                           ^
Q.java:3: error: illegal start of type
^
^
Q.java:4: error: = expected
Q.java:1: error: <identifier> expected
 ^
Q.java:4: error: <identifier> expected
Q.java:1: error: <identifier> expected
      ^
Q.java:4: error: ';' expected
Q.java:1: error: <identifier> expected
       ^
Q.java:4: error: illegal start of type
Q.java:1: error: <identifier> expected
        ^
Q.java:4: error: = expected
Q.java:1: error: <identifier> expected
               ^
Q.java:5: error: '(' expected
Q.java:1: error: class, interface, or enum expected
 ^
Q.java:5: error: <identifier> expected
Q.java:1: error: class, interface, or enum expected
      ^
Q.java:5: error: ';' expected
Q.java:1: error: class, interface, or enum expected
       ^
Q.java:5: error: illegal start of type
Q.java:1: error: class, interface, or enum expected
        ^
Q.java:5: error: = expected
Q.java:1: error: class, interface, or enum expected
               ^
Q.java:5: error: <identifier> expected
Q.java:1: error: class, interface, or enum expected
                      ^
Q.java:5: error: <identifier> expected
Q.java:1: error: class, interface, or enum expected
                                 ^
Q.java:5: error: as of release 5, 'enum' is a keyword, and may not be used as an identifier
Q.java:1: error: class, interface, or enum expected
                                      ^
  (use -source 1.4 or lower to use 'enum' as an identifier)
Q.java:5: error: = expected
Q.java:1: error: class, interface, or enum expected
                                           ^
Q.java:6: error: illegal start of type
                      ^
                      ^
Q.java:7: error: = expected
Q.java:1: error: <identifier> expected
 ^
Q.java:7: error: <identifier> expected
Q.java:1: error: <identifier> expected
      ^
Q.java:7: error: ';' expected
Q.java:1: error: <identifier> expected
       ^
Q.java:7: error: illegal start of type
Q.java:1: error: <identifier> expected
        ^
Q.java:7: error: = expected
Q.java:1: error: <identifier> expected
               ^
Q.java:8: error: '(' expected
Q.java:1: error: class, interface, or enum expected
 ^
Q.java:8: error: <identifier> expected
Q.java:1: error: class, interface, or enum expected
      ^
Q.java:8: error: ';' expected
Q.java:1: error: class, interface, or enum expected
       ^
Q.java:8: error: illegal start of type
Q.java:1: error: class, interface, or enum expected
        ^
Q.java:8: error: = expected
Q.java:1: error: class, interface, or enum expected
               ^
Q.java:8: error: <identifier> expected
Q.java:1: error: class, interface, or enum expected
                      ^
Q.java:8: error: <identifier> expected
Q.java:1: error: class, interface, or enum expected
                                 ^
Q.java:8: error: as of release 5, 'enum' is a keyword, and may not be used as an identifier
Q.java:1: error: class, interface, or enum expected
                                      ^
  (use -source 1.4 or lower to use 'enum' as an identifier)
Q.java:8: error: = expected
Q.java:1: error: class, interface, or enum expected
                                           ^
Q.java:9: error: illegal start of type
                                 ^
                                 ^
Q.java:10: error: = expected
Q.java:1: error: as of release 5, 'enum' is a keyword, and may not be used as an identifier
 ^
Q.java:10: error: <identifier> expected
Q.java:1: error: as of release 5, 'enum' is a keyword, and may not be used as an identifier
      ^
Q.java:10: error: ';' expected
Q.java:1: error: as of release 5, 'enum' is a keyword, and may not be used as an identifier
       ^
Q.java:10: error: illegal start of type
Q.java:1: error: as of release 5, 'enum' is a keyword, and may not be used as an identifier
        ^
Q.java:10: error: = expected
Q.java:1: error: as of release 5, 'enum' is a keyword, and may not be used as an identifier
               ^
Q.java:10: error: = expected
Q.java:1: error: as of release 5, 'enum' is a keyword, and may not be used as an identifier
                       ^
Q.java:10: error: illegal start of type
Q.java:1: error: as of release 5, 'enum' is a keyword, and may not be used as an identifier
                               ^
Q.java:10: error: <identifier> expected
Q.java:1: error: as of release 5, 'enum' is a keyword, and may not be used as an identifier
                                ^
Q.java:10: error: unclosed character literal
Q.java:1: error: as of release 5, 'enum' is a keyword, and may not be used as an identifier
                                  ^
Q.java:10: error: ';' expected
Q.java:1: error: as of release 5, 'enum' is a keyword, and may not be used as an identifier
                                    ^
Q.java:10: error: unclosed character literal
Q.java:1: error: as of release 5, 'enum' is a keyword, and may not be used as an identifier
                                       ^
Q.java:10: error: = expected
Q.java:1: error: as of release 5, 'enum' is a keyword, and may not be used as an identifier
                                                     ^
Q.java:10: error: = expected
Q.java:1: error: as of release 5, 'enum' is a keyword, and may not be used as an identifier
                                                           ^
Q.java:10: error: = expected
Q.java:1: error: as of release 5, 'enum' is a keyword, and may not be used as an identifier
                                                                      ^
Q.java:10: error: = expected
Q.java:1: error: as of release 5, 'enum' is a keyword, and may not be used as an identifier
                                                                                 ^
Q.java:11: error: <identifier> expected
Q.java:1: error: class, interface, or enum expected
      ^
Q.java:11: error: ';' expected
Q.java:1: error: class, interface, or enum expected
       ^
Q.java:11: error: illegal start of type
Q.java:1: error: class, interface, or enum expected
        ^
Q.java:11: error: = expected
Q.java:1: error: class, interface, or enum expected
               ^
Q.java:11: error: <identifier> expected
Q.java:1: error: class, interface, or enum expected
                      ^
Q.java:11: error: <identifier> expected
Q.java:1: error: class, interface, or enum expected
                                 ^
Q.java:11: error: as of release 5, 'enum' is a keyword, and may not be used as an identifier
Q.java:1: error: class, interface, or enum expected
                                      ^
  (use -source 1.4 or lower to use 'enum' as an identifier)
Q.java:11: error: = expected
Q.java:1: error: class, interface, or enum expected
                                           ^
Q.java:12: error: illegal start of type
                                      ^
                                      ^
Q.java:12: error: <identifier> expected
                                      ^
                                       ^
Q.java:13: error: = expected
  (use -source 1.4 or lower to use 'enum' as an identifier)
   ^
Q.java:13: error: ';' expected
  (use -source 1.4 or lower to use 'enum' as an identifier)
      ^
Q.java:13: error: <identifier> expected
  (use -source 1.4 or lower to use 'enum' as an identifier)
              ^
Q.java:13: error: = expected
  (use -source 1.4 or lower to use 'enum' as an identifier)
               ^
Q.java:13: error: ';' expected
  (use -source 1.4 or lower to use 'enum' as an identifier)
                  ^
Q.java:13: error: = expected
  (use -source 1.4 or lower to use 'enum' as an identifier)
                               ^
Q.java:13: error: unclosed character literal
  (use -source 1.4 or lower to use 'enum' as an identifier)
                                   ^
Q.java:13: error: unclosed character literal
  (use -source 1.4 or lower to use 'enum' as an identifier)
                                        ^
Q.java:13: error: = expected
  (use -source 1.4 or lower to use 'enum' as an identifier)
                                                          ^
Q.java:14: error: <identifier> expected
Q.java:1: error: = expected
      ^
Q.java:14: error: ';' expected
Q.java:1: error: = expected
       ^
Q.java:14: error: illegal start of type
Q.java:1: error: = expected
        ^
Q.java:14: error: = expected
Q.java:1: error: = expected
               ^
Q.java:14: error: illegal start of type
Q.java:1: error: = expected
                 ^
Q.java:15: error: = expected
Q.java:1: error: class, interface, or enum expected
^
Q.java:15: error: illegal start of type
Q.java:1: error: class, interface, or enum expected
 ^
Q.java:15: error: = expected
Q.java:1: error: class, interface, or enum expected
      ^
Q.java:15: error: illegal start of type
Q.java:1: error: class, interface, or enum expected
       ^
Q.java:15: error: <identifier> expected
Q.java:1: error: class, interface, or enum expected
        ^
Q.java:15: error: = expected
Q.java:1: error: class, interface, or enum expected
          ^
Q.java:15: error: ';' expected
Q.java:1: error: class, interface, or enum expected
               ^
Q.java:15: error: <identifier> expected
Q.java:1: error: class, interface, or enum expected
                      ^
Q.java:15: error: <identifier> expected
Q.java:1: error: class, interface, or enum expected
                                 ^
Q.java:15: error: as of release 5, 'enum' is a keyword, and may not be used as an identifier
Q.java:1: error: class, interface, or enum expected
                                      ^
  (use -source 1.4 or lower to use 'enum' as an identifier)
Q.java:15: error: = expected
Q.java:1: error: class, interface, or enum expected
                                           ^
Q.java:16: error: illegal start of type
                                           ^
                                           ^
Q.java:17: error: = expected
Q.java:2: error: <identifier> expected
 ^
Q.java:17: error: <identifier> expected
Q.java:2: error: <identifier> expected
      ^
Q.java:17: error: ';' expected
Q.java:2: error: <identifier> expected
       ^
Q.java:17: error: illegal start of type
Q.java:2: error: <identifier> expected
        ^
Q.java:17: error: = expected
Q.java:2: error: <identifier> expected
               ^
100 errors

Answer 14

TrumpScript - Making PPCG Great Again (TrumpScript)

When trying to run this language on a windows PC, the output is always:

Make sure the currently-running OS is not Windows, because we're not PC

So when running this program:

Make sure the currently-running OS is not Windows, because we're not PC

It won't even parse it because the OS check fails, and you get the error message. Examples can be given for Mac as well if anyone wants them haha. God I've wanted to use this in PPCG for awhile now, good that I finally get to.

Full list of errors that can be triggered using environmental specifics:
https://github.com/samshadwell/TrumpScript/blob/master/src/trumpscript/utils.py

---

Bonus Answer: ArnoldC (ArnoldC)

ArnoldC requires root declaration of IT'S SHOWTIME, meaning main(), so:

WHAT THE FUCK DID I DO WRONG

Results in the only error message in ArnoldC...

WHAT THE FUCK DID I DO WRONG

Which, is actually... hilarious. You have to run it non-verbose though w/o stack traces.

Answer 15

ArnoldC

missing IT'S SHOWTIME on first line

Paste the code into this compiler.

Answer 16

Z-machine interpreter

I don't know the word "know".

Test against this popular interpreter. Also there's some sort of mostly harmless game hosted there.

Answer 17

Julia 0.2.0

Another syntax error found iteratively until a fixed point was reached:

ERROR: syntax: extra token "token" after end of expression

Answer 18

Mathematica

Syntax: "needed." is incomplete; more input is needed.

A . in Mathematica means either a decimal point or function Dot. In this case, the . appears at the end of an expression and cannot be interpreted.

---

Answer 19

C

I applied the method of repeatedly copying the error messages to the source. It converged in 2 cycles. Compiled on OSX 10.9 with 'cc -c error.c'.

error.c:1:1: error: unknown type name 'error'
error.c:1:1: error: unknown type name 'error'
^
error.c:1:6: error: expected identifier or '('
error.c:1:1: error: unknown type name 'error'
     ^
2 errors generated.

Note: This is not so much an answer as it is a methodology to get one. The result might change depending on your OS or the version of cc you are using.

The exact method to get the result is to execute the instructions

$ cc -c error.c 2>out ; mv out error.c ; cat error.c

repeatedly until the output stops changing.

Answer 20

INTERCALL, 90 bytes

Fatal error: A INTERCALL program must start with the mandatory header to prevent golfing.\n

Includes a trailing newline at the end. Note that this isn't STDERR, but it was considered to be error output by many, so I posted it here.

This is the "mandatory header":

INTERCALL IS A ANTIGOLFING LANGUAGE
SO THIS HEADER IS HERE TO PREVENT GOLFING IN INTERCALL
THE PROGRAM STARTS HERE:

Answer 21

GHCi (a Haskell interpreter/shell)

Code.hs:1:1: Parse error: naked expression at top level

Usage:

Write the code in a file named Code and load with GHCi.

A nice fact is that, if the words were actual identifiers, this would be a legal expression (as long as it would typecheck). This is basically due to the fact that : is a built in operator, . is used for module-qualified names, and whitespace is used to denote function application.

Answer 22

C++ (g++)

The file must be saved as 1.pas.

g++: error: 1.pas: Pascal compiler not installed on this system

Answer 23

Ruby 2 on Windows

Code:

error.rb:1: syntax error, unexpected tINTEGER, expecting tSTRING_CONTENT or tSTRING_DBEG or tSTRING_DVAR or tSTRING_END
error.rb:1: syntax error, unexpected tI...
          ^

The code was found by testing and iterating the process over and over until a fix-point was reached. The code must be inside the file "error.rb".

Demo:

C:\>type error.rb
error.rb:1: syntax error, unexpected tINTEGER, expecting tSTRING_CONTENT or tSTR
ING_DBEG or tSTRING_DVAR or tSTRING_END
error.rb:1: syntax error, unexpected tI...
          ^

C:\>ruby.exe error.rb
error.rb:1: syntax error, unexpected tINTEGER, expecting tSTRING_CONTENT or tSTR
ING_DBEG or tSTRING_DVAR or tSTRING_END
error.rb:1: syntax error, unexpected tI...
          ^

Answer 24

C (gcc)

error.c:1:6: error: expected ‘=’, ‘,’, ‘;’, ‘asm’ or ‘__attribute__’ before ‘.’ token
 error.c:1:6: error: expected ‘=’, ‘,’, ‘;’, ‘asm’ or ‘__attribute__’ before ‘.’ token
      ^
compilation terminated due to -Wfatal-errors.

Compile with gcc -Wfatal-errors error.c.

Answer 25

Applescript (in Script Editor)

Syntax Error
A "error" can't go after this identifier.

Answer 26

AppleScript

A identifier can’t go after this identifier.

Both A and identifier can be identifiers, so AppleScript says no.

Answer 27

BBC Basic, 7 bytes (or 0 Bytes)

This is a valid 7 byte entry:

Mistake

This is the error message produced by the interpreter when it is completely unable to make sense of the code.

On the other hand, this is not:

ERROR

This is a valid keyword in BBC Basic which is supposed to deliberately introduce an error of a specified code into the program, but the syntax is wrong (no code is given.) Therefore it returns Syntax error (which in turn returns Mistake when it is run.)

In general the procedure described by Falko in his answer leads to Mistake in BBC basic. There are a few exceptions. anything producing the errorsDATA not LOCAL or ON ERROR not LOCAL leads to the famous zero byte quine: an empty source code produces an empty file.

Given that most error messages in BBC basic are lowercase (and therefore not valid keywords) I am pretty sure that any invalid input will ultimately lead to one of these possibilities.

Answer 28

CJam 0.6.2

Syntax error:
java.lang.RuntimeException: y not handled

Try it online.

Answer 29

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 30

x86 assembly

Bytecode:

53 65 67 6d 65 6e 74 61 75 69 6f 6e 20 66 61 75
6c 74 20 28 63 6f 72 65 20 64 75 6d 70 65 64 29

i.e. the text

Segmentation fault (core dumped)

Crashes immediately because the second instruction (the first being just "push %[er]bx") is

insl (%dx), %gs:(%di)

which fails because (a) ins cannot take segment overrides, (b) %dx and %di are almost certainly uninitialized, (c) %di is a 16-bit memory address and therefore can't be accessed in long mode, (d) ins is an invalid instruction outside of real mode.

The exact output may vary depending on what system this is run on, but it is likely that it will contain some form of illegal instruction.

Answer 31

Pepe, 9 bytes

RRRERROR!

Link to interpreter (paste the code above, permalink removes the ! and O)

Explanation:

Like I explained here, the interpreter ignores characters other than R,r,E,e so the code is:

RRRERRR

Now to explain:

  RE    # Push 0
RR      # (RR flag: doesn't exist)
    RRR # There is no command RRR, so output RRRERROR!

Answer 32

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 33

zsh (Linux)

zsh: command not found: zsh:

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

Answer 34

Forth

Try it here

This was surprisingly easy to come up with.

a : error(-13): word not found

Answer 35

Bash

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

Answer 36

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 37

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 38

Malbolge, 32 bytes

invalid character in source file

Try it online!

Answer 39

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 40

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 41

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 42

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 43

(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 44

Javascript (Chrome/V8), 65 41 39 Bytes

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

Try it online!

Answer 45

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 46

Python 3, 28 bytes

SyntaxError: invalid syntax

Answer 47

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 48

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 49

ksh

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

Answer 50

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 51

Java, in Eclipse

Syntax error on tokens, delete these tokens

Answer 52

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 53

MATLAB, 66 bytes

Undefined function 'Undefined' for input arguments of type 'char'.

This outputs the same to STDERR (shown in the console in red):

This is actually pretty unknown functionality (and it's rarely useful), which is why the MATLAB submission in the "Hello World!"-challenge may be improved.

This works because MATLAB will automatically interpret a command on the form <word_1 word_2 word_3 word_4>, with no surrounding brackets, as a function on the form:

word_1('word_2')`

That is, it calls a function word_1 and gives the single input argument after the first, and in front of the second space as a string input to that function.

"Real life"-examples that can be used for golfing:

disp Hello   % Shorter than disp('Hello')
Hello

disp Hello World!
Hello

nnz variable
ans =
     8

Note that it will always interpret it as a string, it will not evaluate it:

variable = 3;
nnz variable
ans =
     8
nnz(variable)
ans =
     1

Answer 54

A Pear Tree

a partridge

Try it online!

Almost every program (that isn't very long) prints a partridge in A Pear Tree.

One of the goals of the language was to be good at polyglot challenges; as such, it tries to find a substring of the program that has a very specific property that rarely occurs by chance, and starts running the program there. If it can't find an appropriate entry point, it prints an error. The actual text of the error message was chosen for the The Twelve Days of Christmas reference. (Actually, the design for the language worked the other way round; the main goal was to have a language which errored out on almost any source code, so that it would make the reference in question, so I set about trying to work out what sort of language design would naturally end up doing that.)

Answer 55

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 56

TI-83/84 Basic

Simple & for your calculator

ERR:SYNTAX

Answer 57

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 58

ForceLang

Works in the latest version of the reference implementation as of the time this answer was written.

Exception in thread "main" lang.exceptions.IllegalInvocationException: Exception is not a function.
    at lang.ForceLang.parse(ForceLang.java:52)
    at lang.ForceLang.main(ForceLang.java:129)

Answer 59

Python 3.5

Note: the source file should be named "1" for this to work

  File "1", line 1
    File "1", line 1
    ^
IndentationError: unexpected indent

Answer 60

GW-BASIC (least: 12 bytes)

Syntax error

Inspired by the Commodore 64 BASIC answer. Knocked off 2 bytes because IBM and DOS are better than Commodore :P You can download an emulator for GW-BASIC.

NEXT without FOR

Since GW-BASIC is a line-based language, it only evaluates the first instruction after a newline or colon :. Therefore, it reads NEXT and automatically fails it didn't read a FOR.

Apple ][ BASIC (13 bytes)

?SYNTAX ERROR

Woo, 1 less byte than the Commodore answer because the old Apples could beat a Commodore anyday :P

QBasic (43 bytes)

Parse failed: Syntax error at 1:1: Token(:)

Might be cheating because it only works on the first line.

Applesoft BASIC (69 bytes)

ParseError: Syntax error: Expected line number or separator in line 0

Also only works on the first line...

Answer 61

sed

By using this general approach, I have converged on several sed error quines. This may not work in your sed, in which case, you're using the wrong sed, and therefore would you please acquire necessary, error-quining sed.

Try it online! This version works in TIO, and probably not anywhere else. Open the "Debug" panel to see the error.

Where sed is macOS's default sed, and gsed is a GNU sed.

Answer 62

Recursiva, 7 bytes

Error!

Try it online!

Answer 63

NASM for x86: 45 bytes

e.asm:1: error: parser: instruction expected

Assemble (or attempt to assemble) with nasm e.asm

Just in case:

0:beau@beau-Latitude-E6330:[~/asm/q]$ nasm -v
NASM version 2.12.02 compiled on Feb  5 2017
0:beau@beau-Latitude-E6330:[~/asm/q]$ 

Answer 64

Ly

Error occurred at program index 3, instruction o (zero-indexed, includes comments)
EmptyStackError: cannot pop from an empty stack

Demo (using official compiler)

This program makes use of the o in "Error", the first instruction character in the error message that produces an error. (apparently r does nothing with an empty stack)

When a stack is not empty, o takes the top entry off the selected stack and outputs it as ASCII; EmptyStackError occurs when the selected stack is empty. So when Ly runs into this o, it causes this error, since we haven't given the stack anything yet.

Answer 65

VB.Net, 32 Bytes

Create a new, empty project named 'A'. Set the startup object to "Sub Main" (it's a drop-down option). Create a new class called anything. Delete everything from the class and copy/paste the following:

'Sub Main' was not found in 'A'.

This works because a single quote is a comment, so it looks like a blank file :D

Answer 66

ESOPUNK, 38 bytes

Invalid instruction INVALID at line 0.

Answer 67

K (ngn/k), 2 bytes

'c

Try it online!

'c is the response from the console indicating that the variable c is undefined

Answer 68

MiLambda

ERROR_NOHALT

Try it online!

Seems like a short solution

Answer 69

ZSH (macOS), 20 bytes excluding newline

 zsh: bad pattern: ^[

Answer 70

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 71

Cobra

test.cobra(1): error: Expecting use, assembly, namespace, class, interface or enum, but got "test".
Compilation failed - 1 error, 0 warnings
Not running due to errors above.

Answer 72

Befunge on Wasabi v1.4

There is an interpreter for Befunge called Wasabi, and when an error appears the error message is in the format of a dialog box. This is the program:

Unsupported Command : 'U' at (1, 0). Ignore next syntax error(s)?

To test, download Wasabi v1.4 and insert the above program.

Answer 73

C++

(Using Apple LLVM in Xcode)

Unknown type name 'Unknown'
Expected ';' after top level declarator

Answer 74

Loader (using the official Java interpreter):

These should be run from a module named main in order to produce the exact error messages given here.

This works in the most recent version of the interpreter:

Error: Could not evaluate expression Error (module main, line 1)

Explanation:

expression:statement is a conditional. The interpreter doesn't even syntax check the stuff to the right of the colon (if it did, we'd get a different error message) unless the stuff on the left evaluates to a nonzero value. However, as "Error" is an illegal expression, the interpreter can't evaluate it, exiting the program with this error message.

In some earlier interpreter versions, this would work instead:

Exception in thread "main" java.lang.RuntimeException: Could not evaluate expression Exception in thread "main" java.lang.RuntimeException (module main,line 1)
    at Loader.expr(Loader.java:183)
    at Loader.load(Loader.java:201)
    at Loader.main(Loader.java:249)

Answer 75

ChucK

Here's my contribution:

[chuck]:line(1).char(8): syntax error

This works if you first type it into the editor, save it as "chuck", and then run it once. If you run it another time the number in char() goes up by eight.

ChucK can be downloaded here.

Answer 76

CJam

Syntax error:
java.lang.RuntimeException: y not handled

Answer 77

JavaScript

Uncaught SyntaxError: Unexpected identifier

Throws a generic Unexpected identifier error (in Chrome, at least) because it doesn't recognize Uncaught as an identifier.

Answer 78

Codelike, 36 Bytes

Error at (1,1): Unknown character: E

Try it!

Answer 79

Ada

test.adb:1:01: compilation unit expected

Really just make an ada file, toss it at the start as above and compile with gcc filename.adb -c.

Answer 80

Go

Try it with this embedded repl.it page:

<script src="//repl.it/embed/Ew1N/0.js"></script>

Answer 81

Syms, 202 bytes

Traceback (most recent call last):
  File "/opt/syms/syms.py", line 196, in <module>
    stack.append(("{"+str(stack.pop())+"}").replace("\\","\\\\").replace("&","\\&"))
IndexError: pop from empty list

Try it online! Works on TIO. May not work on your configuration.

Answer 82

KSH script, 48 bytes

Save as a file named k.

k[1]: not: not found [No such file or directory]

Try it online! Note that TIO saves KSH scripts as .code.tio, so it's a bit longer but still the same thing.

Answer 83

k, oK

Might as well group these answers together, since it's supposedly the same language. I must say, this general approach is quite versatile.

oK

Every error seems to have a lot of environment-specific information, because, well, JavaScript is behind it all. Try it online!

/opt/ok/oK.js:876
    throw new Error("unexpected character '"+text[0]+"'");
    ^

Error: unexpected character ')'
    at Object.parse (/opt/ok/oK.js:876:8)
    at Object.<anonymous> (/opt/ok/repl.js:62:43)
    at Module._compile (module.js:570:32)
    at Object.Module._extensions..js (module.js:579:10)
    at Module.load (module.js:487:32)
    at tryModuleLoad (module.js:446:12)
    at Function.Module._load (module.js:438:3)
    at Module.runMain (module.js:604:10)
    at run (bootstrap_node.js:390:7)
    at startup (bootstrap_node.js:150:9)

k

Notice the space at the bottom. This works in 2016.06.28 (c) arthur whitney version of kmac.

a
^
value error
 

Answer 84

Python 3

  File ".py", line 1
    File ".py", line 1
    ^
IndentationError: unexpected indent

Answer 85

Turing Machine But Way Worse, 258 bytes

Traceback (most recent call last):
  File "/opt/tmbww/TuringMachineButWayWorse.py", line 16, in <module>
    i[0], i[2], i[3], i[5], i[6] =  int(i[0]), int(i[2]), int(i[3]), int(i[5]), int(i[6])
ValueError: invalid literal for int() with base 10: 'Traceback'

Try it online!

Answer 86

ink, 65 bytes

ERROR: 'q' line 1: Empty diverts (->) are only valid on choices

Try it online!

Must be saved in a file called q, which is why the code on TIO is 7 bytes longer.

Answer 87

Snowman, 121 bytes

SnowmanException thrown at tokenize
  what():  at tokenize: letter operator terminated prematurely?
fatal error, aborting

Try it online!

Answer 88

W.Y.A.L.H.E.I.N., 253 bytes

Traceback (most recent call last):
  File "/opt/wyalhein/whenyouaccidentallylose100endorsementsinnationstates.py", line 6, in <module>
    seed = int(contents[0])
ValueError: invalid literal for int() with base 10: 'Traceback (most recent call last):\n'

Try it online!

whenyouaccidentallyloseahundredendorsementsinnationstates expects a seed on the first line, and Traceback (most recent call last): is not a valid number (unless we're talking in base 96, of course, but whenyouaccidentallyloseahundredendorsementsinnationstates doesn't).

Answer 89

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!

Answer 90

33

Very simple. : isn't a valid command, so it's easy to make an unrecognised token error quine. The error is just where the : is in the code.

33 (1:8): Unrecognised token

Answer 91

GNU Smalltalk REPL

REPL is always acceptable, and I only learned the Smalltalk REPL and don't know how to save programs in a file. (I think TIO does not have Smalltalk yet.)

stdin:1: expected expression

This will work when you start the REPL for the first time.

Answer 92

C (tcc), 42 bytes

.code.tio.c:1: error: declaration expected

Try it online!

Answer 93

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 94

MS SQL (Server version 2012), 64 bytes

Msg 2812, Level 16, State 62, Line 1
Incorrect syntax near '16'.

Answer 95

CJam, 12 bytes

u not handled

When operator doesn't exist, interpreter prints * not handled

Answer 96

Straw

/opt/straw/straw.rb:108:in `initialize': no implicit conversion of nil into String (TypeError)
    from /opt/straw/straw.rb:108:in `new'
    from /opt/straw/straw.rb:108:in `step'
    from /opt/straw/straw.rb:225:in `run'
    from /opt/straw/straw.rb:254:in `<main>'

Try It Online!

Answer 97

Elixir

== Compilation error on file e.ex ==
** (SyntaxError) e.ex:3: keyword argument must be followed by space after: ex:
    (elixir) lib/kernel/parallel_compiler.ex:114: anonymous fn/4 in Kernel.ParallelCompiler.spawn_compilers/1

Put the code in e.ex and compile with elixirc e.ex. There are also some blank lines in the output (and in the file), but I can't get them to appear on here; S.O. eats them.

Answer 98

F#

e.fs(1,11): error FS0010: Unexpected symbol ':' in implementation file

Compile with fsc --nologo e.fs. Again, there's an extra blank line I can't properly reproduce here. (Without the --nologo flag the compiler wants to announce itself and its version number and display a Microsoft copyright message.)

Answer 99

><>, 25 bytes

something smells fishy...

Try it online!

Explanation

The only error in ><> is something smells fishy....