The most copied StackOverflow snippet of all time is flawed

It turns out when you can package snippets you use so many you can't possibly keep track and audit them all.

Just look at the Left-pad thing, or the event-stream thing.

“I see you used “for i in...” and that copies this SO question about iteration...”

> I qualitatively analyzed the top 50 clones in that list and was able to identify the source (or at least a source) of the snippets in most of the cases.

[1]: https://meta.stackoverflow.com/questions/375761/how-to-handl...

The article even mentions:

> FWIW, all 22 answers posted, including the ones using Apache Commons and Android libraries, had this bug (or a variation of it) at the time of writing.

You run into the same problem if you are writing something like the C 'itoa' function (integer to ascii); if you want to write the digits out front to back you need to know what divisor to use for the leading digit so you need to either look it up in a table or take the log.

Taking the log is a lot slower than the table lookup, I found that out the hard way.

People convert so many integers to ascii and it is shocking how slow ascii <-> binary numeric conversions are compared to binary numeric operations, so it's not a matter of "premature optimizations".

Now you can write an itoa which generates the digits from back to front and not have to worry about copying the results because you return a pointer to the middle of the result buffer but then memory management gets more complex...

Rust has a nice solution for this though: tests can also be embedded in documentation comments:

    /// Adds one to the number given.
    ///
    /// # Examples
    ///
    /// ```
    /// let arg = 5;
    /// let answer = my_crate::add_one(arg);
    ///
    /// assert_eq!(6, answer);
    /// ```
    pub fn add_one(x: i32) -> i32 {
        x + 1
    }

More languages could adopt that idea, and a good StackOverflow answer would include those tests in the snippet. StackOverflow might even automatically run the tests and add a passing/failing badge!

Rather, I think this is an argument that this kind of functionality should be in the standard library; perhaps in the equivalent of `*printf` for each language.

https://www.zdnet.com/article/two-malicious-python-libraries...

Ironic that this was published today. :-)

Random code snippets from the internet are obviously completely unsafe. There is therefore basic "due diligence" to apply when considering using one such snippet:

1. Very carefully read the code to understand it.

2. Test it (corner cases/threshold values are the trivial things to test for such a piece of code doing conversions)

In general I do not copy-paste code snippets. I use them as examples of how to perform a task or how to use an API, then I write my own code. This also avoids IP issues.

The Software Freedom Law Center has a substantial article on copyrightability of code: https://softwarefreedom.org/resources/2007/originality-requi...

The important point here is that there's no minimum length for code to be copyrightable. It simply needs to be original and at least minimally creative. Since at least thousands of other developers have found the snippet to be useful enough to directly borrow rather than writing an equivalent, it sure looks copyrightable to me.

I'm not a professional developer, but I've copied snippets from SO before. I've always included the answer URL in a comment next to it though. But mostly because if I ever had issues with it, I wanted to know where I got it and on the off chance anyone else looks at my code, I wouldn't want them thinking I wrote code I didn't write.

You'd be violating the ToS.

It should always use the highest relevant prefix to avoid confusion imho.

Have you ever used the "examples" section of a man page or do you prefer to scroll through the (sometimes long) list of parameters?

In my opinion, code examples are an important tool for teaching real-life usage patterns.