125
votes
Things to avoid when writing challenges
Cumbersome I/O formats
Generally, allow flexible input and output formats. People want to write code to do your task of, say, composing permutations, not reading/writing numbers in a particular ...
- 144k
85
votes
Things to avoid when writing challenges
Rules inferred from test cases
Test cases are examples for people to check their understanding of the spec and the correctness of their code. They should not replace an explanation of how the output ...
- 144k
79
votes
Things to avoid when writing challenges
Making assumptions about language features
Unless you're writing a language-specific challenge, avoid terms specific to some class of languages, because these might not make sense for other languages ...
- 144k
75
votes
Things to avoid when writing challenges
Changing the challenge in the comments
If something was unspecified in your challenge, or if you've decided to make a change to the challenge (Such as to close a loophole), don't just leave a comment....
- 42k
75
votes
Things to avoid when writing challenges
Bonuses in code golf
Digital Trauma wrote an answer about this, but I have harsher views on bonuses, so I'm posting to let people vote separately.
Bonuses in code golf say things like "-30% of your ...
- 144k
74
votes
Things to avoid when writing challenges
Do X without Y
This isn't always bad, but it's been a particular trap for beginners, so be careful.
In the past, there were popular questions about doing a simple task but with the obvious method ...
- 144k
71
votes
Things to avoid when writing challenges
Explicitly disallowing or disadvantaging arbitrary (classes of) languages
This has become much rarer recently, but the occasional challenge by a new user still includes it, so here as an answer to ...
- 196k
63
votes
Things to avoid when writing challenges
Putting test cases in a hard to use format
Supplying test cases is always a good idea, but people are more likely to use them (and thus have better tested code) if they can easily be copied and pasted ...
- 89.3k
59
votes
Things to avoid when writing challenges
Requiring minimum scores
In short, don't post a code golf that says "Your code has to be shorter than 100 bytes" (the same applies to any other winning criterion). The usual motivation is that the ...
- 196k
57
votes
Things to avoid when writing challenges
Chameleon challenges
Chameleon challenges look like they're about one thing but are really about another. In doing the challenge, most of the effort is spent on something peripheral. Fix this by ...
- 144k
52
votes
Things to avoid when writing challenges
Non-observable program requirements
The validity of a program should depend on things that can be observed when the program is treated as a black box. Examples are data written to standard output or ...
- 31.3k
51
votes
Things to avoid when writing challenges
Don't allow / ask for different things in languages with different capabilities
Don't write specs like "Do X. If your language doesn't support X, you can do Y instead". Examples are:
Do some math in ...
- 35.8k
51
votes
Accepted
Should answers have to handle invalid inputs?
No, invalid inputs may result in undefined behavior
Requiring input validation only adds extraneous code to the answer and takes away from the challenge.
- 28.9k
45
votes
Things to avoid when writing challenges
"Ideally, your code will..."
Avoid recommended features in your spec. If it's not mandatory, answers won't do it. The goal is to write the shortest/fastest/winningest code that still satisfies the ...
- 144k
44
votes
Things to avoid when writing challenges
Arbitrarily overriding the defaults
The default code formats, input/output methods, and other defaults are a product of community thought and discussion. Don't change them just because you feel like ...
- 144k
44
votes
Things to avoid when writing challenges
Saying you should produce one or several outputs randomly without further specification
One random output
Say someone writes a challenge about generating a labyrinth of a given size (width and height) ...
- 104k
43
votes
Things to avoid when writing challenges
Requiring the use of unnecessarily "complicated" number types
A large proportion of our challenges deal with numbers, or lists of numbers. An important consideration is always what sort of numbers ...
- 196k
37
votes
Things to avoid when writing challenges
Allowing standard loopholes in general
Don't say "Standard loopholes are allowed". They ban silly things like making up a language where the solution is a single character or just printing the string ...
- 144k
37
votes
Things to avoid when writing challenges
The prime numbers
We have 226 questions about prime numbers at the time of writing. Almost every single one of these involves some adaptation of the “canonical prime checking code” or the “canonical ...
- 68.1k
37
votes
Things to avoid when writing challenges
Formulating the challenge as something and then including a twist that completely changes the task
Don't hide information from the reader. Don't enounce the challenge as something that later on it ...
- 104k
36
votes
Things to avoid when writing challenges
Most kinds of generalised quines
Quines continue to fascinate this community... but we already have a plain quine challenge so we're "forced" to innovate by making quine-related challenges that aren'...
- 196k
34
votes
Things to avoid when writing challenges
Adding unnecessary fluff
See also: Chameleon challenges, Cumbersome I/O formats, Do X without Y
What's the main point of the challenge? Try to keep the challenge to just that. Don't go adding frills ...
- 61.7k
33
votes
Things to avoid when writing challenges
Patching out approaches
On your challenge, someone posts a solution that's cheap and not at all what you intended. You have the option to change the rules, but do so very carefully as there's many ...
- 144k
32
votes
Things to avoid when writing challenges
Input Validation
This is a subset of adding special cases for completeness that seems to come up pretty often. From a given set of possible inputs, a solution shouldn't have to sort out inputs that ...
Jo KingMod
- 47.1k
28
votes
Things to avoid when writing challenges
Popularity Contests
Popularity contests, while allowed, are heavily disfavored by site culture. You're likely better off reworking your challenge to use an objective winning criterion that isn't ...
- 144k
27
votes
Accepted
The state of the popularity contest tag
Keep It, but...
...we should definitely update e.g. the tag info. The recent discussions have not been unproductive, and I think we have better guidelines than ever before but at the moment they are ...
- 43.7k
24
votes
Things to avoid when writing challenges
Hidden pattern in the output for code golf challenges
You should not post a challenge in which an essential part is to find a pattern in the required output, which is not stated in the challenge but ...
- 104k
23
votes
Things to avoid when writing challenges
Bonuses in code-golf
This might be controversial - Personally I'm not sure which way to go on this one.
In most cases, code-golf scoring is simple - shortest answer in bytes wins.
However some ...
- 71.8k
Only top scored, non community-wiki answers of a minimum length are eligible