Auto-detection of non-indented code

Question

By far the most common edit that I have to make in SO is to correct newbie users who don't know how to format their code. This got me thinking: is there a way to automatically recognize when a post contains unindented code and present the asker with a popup or warning message? Simply pointing out that their code isn't formatted and pointing to the format button would go a long ways towards cutting down the difficulty that new users have. A relatively simple Bayesian classifier could probably catch enough cases to be useful.

I welcome implementation discussion and counter-proposals in the answers.

Answer 1

Per

Simple method for reliably detecting code in text?

We just deployed a method that we think is quite reliable for blocking 98% of posts submitted with code that has improper code formatting (or no code formatting at all).

For example, when I go into Chrome incognito and attempt to ask this question body on Stack Overflow right now:

I needed to add up all the rows for a result. Using the select_sum as follows

Here is the model

function Dues_Paid_Tot($date)
    {
        $query = $this->db->select_sum('Dues_Paid', 'Dues_Paid_Tot');
        $query = $this->db->get('Membership');
        return $query->result();
    }

Here is the controller

function Fiscal2()
    {
    $date = $this->input->post('Select_Date');
        if($query = $this->report_model->fiscal_list($date))
        {
            $data['records'] = $query;
        }
    $data['date'] = $this->input->post('Select_Date');
    $data['Dues_Paid_Tot'] = $this->report_model->Dues_Paid_Tot($date);
    $data['main_content'] = 'report_fiscal_view';
    $this->load->view('includes/template', $data);
}

I get back:

Oops! Your question couldn't be submitted because:

Your post appears to contain code that is not properly formatted as code. Please indent all code by 4 spaces using the code toolbar button or the CTRL+K keyboard shortcut. For more editing help, click the [?] toolbar icon.

This check is limited to users with <= 50 reputation and is performed on questions / answers / edits and suggested edits.

If you see or hear of any cases where this is triggered inappropriately -- or not triggered, and it should have been -- let us know.

Answer 2

A scan of the post to see if it contained common keywords outside coding markup might work, though it would have to be just a hint ("Your post looks like it contains code, have you formatted it correctly") rather than a popup.

However, there are many potential languages - c#, c++, XML, XAML, VB, php, perl, etc. and what's common in one is rare in another and a superset of all languages might generate a lot of false positives.

Answer 3

I think a common pattern for "code-looking text" might be "a bunch of short(ish) lines with a newline at the end of each one". Especially if there's any kind of other indent structure.

Answer 4

I think our best bet is going to continue to train new users in the preferred ways of the community, especially after Jeff's latest blog post on user myopia. I'm a bit with Jeff in "where do we draw the line"?

Answer 5

I'm inclined to agree with ChrisF -- this will likely cause too many false positives. A good heuristic for this that didn't miss any, across the gazillion languages (Ook, anyone?), and was performant and non-intrusive to users ... That'd be a Holy Grail.

How does the heuristic determine inline code (I'm talking about using object.ToString()?) from real code? (I suppose the tick-marks help, but still.) I can think of a variety of situations where code may not even include language keywords -- with as much abstraction as we use these days, it's entirely plausible to have a code block which falls into this. These are just two of the traps.

Not to mention that we're talking hard-core string analysis on posts which can be a couple K ... Every post ... Which happens on SO, what, about every second or so?

No, I think in this case, the "cure" may indeed be worse than the illness. Anyway, I'm working on a Strunk & White here! :)

Answer 6

Ha. I've been on SO for 5+ years and only today have I discovered the { } button (after reading about it on a blog post). I had been indenting my code in my local editor all this time.

Maybe the problem is that said button is just too easy to overlook. I've posted a proposal on how to remedy that.