I recently learned, from a comment by an editor, that questions like
I'm looking for a reference to the literature on how to do X.
I ask myself "why???". How is a request for a reference to the literature on a particular subject any different from asking for help with, e.g., how to remove all the duplicates from a list while preserving the original ordering in Python? Both questions have short, simple, unambiguous answers. Both will receive several alternative answers, and in both cases the desirability of the proposed answers will vary in the OP's opinion, so he/she will be able to mark one of the answers given as the accepted. In both cases a good answer can save the OP a lot of time. In both cases, future users of the site can benefit from the information posted.
Importantly, in both cases the answers will likely be given without any further justification. In both cases, the answers reflect the subjective preferences of the responders, and there's nothing wrong with that, in either case.
Not long ago I made several posts to Stack Overflow, all stemming from difficulties I was having grasping Java generics. (I had read the online tutorials on Java generics, etc., but I still could not write the simplest stuff with them.) In at least one of those posts I added, as a side-note, a request for a solid reference, aimed at experienced programmers (i.e. not a tutorial) that would give me the info I needed to answer my questions by myself. I got no such reference (which now makes sense, since it would have been against the site's mores). Instead I got long, detailed, downright generous replies that, nonetheless, failed to clarify Java generics for me. At best I was getting a fish, when what I wanted was to learn to fish.
Now I can say that I know, with full certainty, why these generous replies failed: the subject of Java generics is far too complex to be adequately explained within the format of an SE post!
It turns out that, well after posting those questions, by dumb luck (browsing in a brick-and-mortar bookstore) I found a book that does a marvelous the job of bringing an experienced programmer up to speed with Java generics, but to do this the author requires 30+ tightly written pages (two chapters). I'm talking 30+ pages with zero fluff: no warm-up examples, no tutorials, just the brass tacks: either stuff digested from the language spec, or capsules of highly abbreviated Java code illustrating the subtler points. And one needs pretty much all of it to fully make sense of Java generics, and use them without resorting to trial-and-error, guesswork, and/or a combination of Google + cut-and-paste + prayer.
Seriously: a single reference to this book would have been far more helpful to me than all the generous replies that I got on SE to all those questions combined. (I feel bad for all those who took the time to write them.)
My point with this anecdote is to illustrate that there are questions for which the best answer by far really is a very specific reference to a book (as in "study chapters 10 and 11 of such-and-such") or a scholarly article.
And what is wrong with that? How is SE's value as a resource in any way diminished by such a reply? Why isn't it, on the contrary, enhanced by it? And if there is nothing wrong with such a reply, then what is wrong with a question that asks for such a reply to begin with?
I know, SE is a privately owned family of sites, not a democracy, and the owners can set it up however they want, end of story. I don't expect to change their minds. But I would like to at least understand the rationale. At the moment it looks at best capricious, at worst, well, ... let's keep this "constructive".
Also, at times it is difficult for me to tell what is actually part of the site's official policy, and what is nothing more than the flawed/biased interpretation of it by some. I noticed that the one of the links I was given to back up this alleged policy, and which is a post to meta.programmers.SE, garnered a rather paltry total of 2 votes. In contrast, some threads on SO on the subject of books have vote counts through the roof. FWIW.
Perhaps the nut of the problem is the contradiction that exists between the often repeated official claim that the rules imposed on SE stem from a desire to make the site useful to its users, coupled with an iron unwillingness to let the users decide (with their votes and page views) what is it that they find useful. It's not the only internal contradiction in SE's policies, but IMO it's the one most likely to generate confusion and frustration.
How should I specify a grammar for a parser? on Programmers
Ref request: where to learn to specify a grammar for a parser? on Stack Overflow
Ref request: grammar specification how-to on Theoretical Computer Science