Cleaning up the vague [function] tag

Question

function is, in my opinion, an incredibly vague tag, that overlaps significantly with functional-programming. The tag wiki of function only has an excerpt that reads

For challenges that ask for a function or involve functions in some way. (Also known as methods or subroutines.)

Taking a browse through the 48 function questions, they can be sorted into 3 categories:

• Questions that ask answerers to submit a function as their solution. If this is the intended usage of function, then it makes it a meta tag, and this already falls under our program defaults (functions and programs)
• Questions that fall under the functional-programming tag, such as this
• Questions that ask answerers to craft a mathematical function with specific requirements. For example, this and this.

The first and second categories should not be appropriate usage of function. They are covered by our site defaults, and the functional-programming tag, respectively.

The third is a legitimate style of question that we should welcome on the site. I also think this was the original usage of the function tag. However, it's currently being confused with other, more vague uses of the word "function". As suggested by Bubbler, mathematical-function or similar would be a better name.

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This discussion is to answer the following questions:

• Should we clean up the function tag?
• If so, how?
  • Should we remove it from posts in category 1, synonymize function with functional-programming and tag relevant questions with a new mathematical-function tag?
  • Something else?

What are your thoughts on the matter?

Answer 1

This is not a complete answer but some thoughts that wouldn't fit in a comment.

I don't think that mathematical-function is a very good name.

The challenges in category 3 have an interesting unifying feature: the fact that they don't mandate particular outputs, but require some property to be true. They do all involve mathematical functions, because mathematical functions are a good language to describe properties. They are not about functions as much as they are about properties. There are many other challenges that do involve mathematical functions or are even about a particular mathematical function (e.g. Fibonacci, factorial etc.). Anything with math has a high probability of involving mathematical functions.

I think calling it mathematical-function, just creates another tag with a vague name, which may very well end up slapped on all sorts of stuff.

The posts here have an interesting unifying feature that not all function related challenges have. So our tag should have a name that captures this feature.

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I suggest open-ended-function

I think the key feature we want though is a name that doesn't cause people to jump to the wrong conclusion and end up tagging a bunch of random challenges. This makes the tag useless.

For these reasons I suggest open-ended-function. This expresses the open-endedness that unifies them and is hard to misinterpret as something else. It probably isn't clear at first sight what this means, but I think that just means newbies click on the tag to read the description, while experienced users will just know what it means.

Answer 2

Create define-function and blackbox-function

I agree with Wheat Wizard in that mathematical-function is vague. For questions that require defining/finding mathematical functions that meet some critera, define-function may be a better name.

There are also some questions that involve taking blackbox functions as input but don't have to do with functional programming. If there are enough of them, I think the tag blackbox-function would be appropriate.