Shortest Error Message

Question

Challenge

Write the shortest program that, when compiled or executed, produces a fatal error message smaller than the program itself. The error message may not be generated by the program itself, such as Python's raise. A valid answer must include both the code and the error message. Shortest valid answer wins.

No error message does not count as an error message.

Example (Lua)

Code (46 bytes):

[
--aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa

Error (45 bytes):

[string "[..."]:1: unexpected symbol near '['

Answer 1

Zsh, 24 bytes

"" #lots of wasted space

Outputs zsh: permission denied:.

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Answer 2

Tcl/Tk, 19

pack [text .text 1]

outputs

18

unknown option "1"

Answer 3

Tcl, 15

if 1234567890/0

outputs

divide by zero

Answer 4

Ly, 77 bytes

[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[

Outputs:

Error occurred during parsing
SyntaxError: unmatched [] brackets in program

(note the trailing newline)

Answer 5

Python 2, 67 bytes

b(h)#This has to be 67 characters. Thus, I'm writing this bullshit.

Error message, 66 bytes

  File ".", line 1, in <module>
NameError: name 'b' is not defined

Note: doesn't work on TIO. Gives a longer error message. Try Python 2.7.13 on a local machine from stdin.

Answer 6

Batch, 24 23 bytes

@dir                  /

Outputs the following 23 22-byte error (as calculated by redirecting the output to a file):

Invalid switch - "".

Edit: Saved 1 byte by not having a switch character at all.

Answer 7

4, 14 bytes

3.141592653589

All 4 programs must start with 3. and end with 4.

Provides as error (when run with the provided python interpreter)

Code invalid.

Answer 8

Mathematica kernel, 36 bytes

ClearAll[f];(*Space Filler*)On[f::f]

and the error is 35 bytes:

(linebreak)On::none: Message f::f not found.(linebreak)
   

Answer 9

Applesoft BASIC, 14 bytes

SYNTAX ERROR??

Output:

?SYNTAX ERROR

Answer 10

ExtraC, 21 bytes

Invalid character: : 

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If you remove the space after the second :it is a error quine

Answer 11

Javascript 79 bytes

clear(this);
a=0;
typein:2: TyperError: attempt to run compile-and-go script on a

Answer 12

C++ (MinGW + GCC + Windows), compile time, 38 39 46 bytes

According to OP's comment, it seems OK to assume the file is stored in a designated path. The code needs to be saved in a 8-byte location such as D:\a.cpp.

#if 1/*aaaaaaaaaaaaaaaaaaaaaaaaaaaaa*/

Error message:

D:\a.cpp:1:0: error: unterminated #if

The principle should work on other platforms.

Answer 13

PHP, 47 Bytes

<?php echo 'program including divide by 0',1/0;

produces:

PHP Warning: Division by zero in - on line 1 plus a newline.

Answer 14

Vim, 19 bytes?

:print "ex command

With a trailing newline, this prints the current line to the messages window. If the buffer is empty, it shows E749: empty buffer instead. The " starts a comment.

I'm an very unsure how to count the number of bytes both in the input and error message. The command can be run as vim +"print \"ex command" (17 bytes?), but this adds an additional line to the error message: Error detected while processing command line: (total 62 bytes?).

Alternatively, the command can be put in a file and run the the following hack to trick Vim it is user input: cat cmd.vim - | vim --not-a-term. Without --not-a-term Vim writes Vim: Warning: Input is not from a terminal.

I didn't count the error message length including a newline since Vim won't write a newline to the screen; it uses ncurses or similar to directly draw at specific coordinates.

There is one potentially shorter error message: E572: Exit code %d. It can be triggered by :tcl, but I'll leave it to someone who has +tcl enabled.

Answer 15

><>, 26 Bytes

Code: "we'refinehereuntilthis!"z

Error: Something smells fishy...

All ><> errors are Something smells fishy...

Answer 16

JavaScript, 13 bytes

prompt(alert(

Error produced (12 bytes):

Expected ')'

Answer 17

Julia 0.6 (REPL/-e), 20 bytes

print(factorial(-9))

produces:

ERROR: DomainError:

(assuming stacktraces don't count) which is 19 bytes.

---

Older answer, 22 bytes:

println(Int(Inf)+0123)

Produces

ERROR: InexactError()

which is 21 bytes.

---

Trivial answer, 7 bytes (probably falls short of "The error message may not be generated by the program itself, such as Python's raise" requirement):

error()

produces

ERROR:

Answer 18

Attache, 40 bytes

A Reference Error: Undefined variable!!!

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Message (39 bytes): Reference Error: Undefined variable "A"

Answer 19

Go, 36 bytes

package verylongnamednonmainpackage;

Produces:

go run: cannot run non-main package

Answer 20

F#, 29 bytes code, 28 bytes error message

let [<EntryPoint>] main a=1/0

Generates the runtime Exception message:

Attempted to divide by zero.

+5 bytes thanks to lukass.

Answer 21

Coconut, 48 bytes

Code:

+
CoconutParsererErrorr: parsing failed (line 1)

Prints error (47 bytes):

CoconutParseError: parsing failed (line 1)
  +

with a trailing newline

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Answer 22

Loader, 50 bytes

load t
This is line not executed because of error.

Assumptions:

• The program is run from a file with a one-byte name
• The module named t does not exist.

The error message (assuming you run from a module named m) is:

Error: module t does not exist (module m, line 1)

Answer 23

C# .NET, 59 bytes

public class P{static void Main(){int je=0;int iee=je/je;}}

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Produces the following error (58 bytes):

System.DivideByZeroException: Attempted to divide by zero.

(NOTE: I am not counting in the stacktrace that the .NET Compiler generates)

Answer 24

Python, 30 bytes

import math as ma; ma.sqrt(-1)

Error: ValueError: math domain error (29 bytes)

Answer 25

GNU Smalltalk, 26 bytes

Create a source file _ with underscores:

__________________________

Running gst _, the error is 25 bytes including ␤:

_:1: expected expression

Underscore was originally mapped to ←, the assignment operator prior to :=.

Answer 26

C, Bionic libc (Android, Termux), 16 characters

main(){free(1);}

Output, 8 characters (including newline)

Aborted

Answer 27

Python, 35 bytes

Pretty simple.

print(a)###########################

Prints out an undeclared variable then adds a comment to make sure that the error message (NameError: name 'a' is not defined) is shorter than the actual code. I could've probably done better.

Answer 28

Whitespace (wspace 0.3), 19 bytes

SSSSL
SLS
TSTS
TLST
LLL

Error: w: divide by zero (18 bytes)

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The zero divisor error is the shortest error message produced by the wspace 0.3 reference interpreter (see the yspace project for a survey of other errors). Using mod in place of div would yield an equivalent result. The reference interpreter was written in Haskell, so arithmetic operations are evaluated lazily and it will not panic with divide by zero unless the illegal value is used by an eager instruction—printi in this case. To reach the minimum byte count, push 0 is written as SSSSL and end is appended.

push 0
dup
div
printi
end

Renaming wspace to w gives a shorter error message.

$ ln -s ~/bin/wspace w
$ ./w codegolf/shortest_error.ws
w: divide by zero
$ ./w shortest_error.ws 2>| wc -c
      18
$ wc -c < shortest_error.ws
      19

(This solution is part of the ws-challenges repo)

Answer 29

Raku (Perl 6) (rakudo), 38 bytes

die#iaj zav; xbsio la, n v km l s zioa

When run using raku -e, this produces the 37-byte output

Died
  in block <unit> at -e line 1

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