Is the tag [reinventing-the-wheel] really helpful?

Question

So I just stumbled upon the tag reinventing-the-wheel and I ask myself if this is really a helpful tag. Most of the code on Code Review does reinvent the wheel in one way or another, there is nearly always a library out there which does that thing already, and maybe better.

Given that new users will barely know about this tag and the tag, according to it's wiki, is only used as a "don't suggest libraries" marker, I'd like to suggest another approach:

• Code on CR should be reviewed, even if we know that there's a library which already does that.
• Pointing out said library is supposed to be a comment or part of an answer reviewing the code.
• Answers only pointing to a library need to be elaborate on how it will fit this use case and how the library is to be used in that case.

Ideally a question should have multiple answers anyway, showing different point of views, and "use a library" should be part of it.

What I've seen so far is that if an asker knows there's a library function to do that, there's normally a paragraph included about why the function has been rewritten (does not meet my use-case completely, only training, etc.), which does tell us much more than that tag.

So...is this tag really helpful?

Answer 1

Yes, the tag is helpful. I consider it to be useful in the same way beginner is useful.

reinventing-the-wheel is for when:

• you are specifically trying to mimic some system/behaviour
• you know that there are libraries, language features, etc. that do what you need.
• you are doing it for academic reasons... to learn, not to profit.
• there is no expectation that this will be 'production' code.

It means that:

• offering alternative implementations for the process is not constructive.
• the desire is to reproduce specific functionality, and that is an indication of the specification for the task.
• there is no 'goal' for the code, it is not trying to solve a specific problem, so there is no 'big picture' problem
• it means that the reviewer should approach things from a slightly different perspective... you are not finding a better way to do things, you are educating the asker as to how they are, or are not meeting the implementation they are trying to reinvent.

Answer 2

I have to bring up this question again, because I really don't think it is that helpful.

Why is it not helpful?

Because it isn't being used that much!

A search for questions with the words "linked list" and without this tag gave a whooping 356 results. Compared to only 3 results that are actually using the tag.

I think that it is a lot more helpful to explicitly say in your question that "I am aware that library XYZ can do this" or that you "Are trying to learn and wanted to make an implementation of XYZ", than tagging a post reinventing-the-wheel.

even if the tag is used on the question, it is still more helpful to write it explicitly in your question.

Therefore I say:

NO, this tag is not helpful!

Answer 3

I made this comment several months ago:

Moderators can do their best to ensure it's used as intended. On SO, I remove the xcode tag from posts about 10 times per day. My question would be whether or not this tag is applicable when rolfl's point 1 applies but point 2 does not.

The two points I'm referencing here are these:

1. you are specifically trying to mimic some system/behaviour
2. you know that there are libraries, language features, etc. that do what you need.

I think the 3rd and 4th points in rolfl's answer are always irrelevant. I think that point 2 might be irrelevant also. If reinventing-the-wheel is going to stay, what's wrong with using it when trying to implement something that already exists, but there's not an available way of implementing it (to your knowledge) without writing the code from scratch?

For example, take the alerts that pop up on an iPhone. Let's say you want to be able to specify the location and background color of the alert (two things I don't think can be done with the UIAlertView class which produces the standard looking alerts). You've written some code to produce your own custom alert which acts exactly like the default iOS alerts... it just looks different. Does this count as reinventing-the-wheel? It certainly falls under point 1... but it doesn't necessarily fall under point 2, because for argument's sake, there's not a library on github that does this to my knowledge. Perhaps I'm trying to develop the first open-source library that lets me do this.

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Now, independent of that question, let's look at a case where points 1 and 2 actually both apply. It just so happens that on github I've written a library for connecting Objective-C applications to MS SQL Server. I also know that there is at least one other library out there on github that existed before mine.

The idea of the reinventing-the-wheel tag seems to be "Hey, don't post an answer linking me to another library!"

In this specific case, I am beyond confident that my library is better in every aspect than the already existing library. Should I be obligated to tag my question with reinventing-the-wheel to prevent answers which link me to the inferior library?

The problem with answers that say "Hey, someone already did this for you!" is that they tend to not actually review the posted code, and they tend to make no effort to demonstrate why the library they link to is actually better than the posted code.

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These points are made mostly for discussion, but particularly in light of my last point, I feel that reinventing-the-wheel should be burninated, and questions that do no more than link to an existing library and say "You should just use this instead" (without explaining why that library is better than the code asking to be reviewed) should be deleted as non-answers.