Re: [PATCH 3/4] merge options: add a conflict style member

On Fri, Mar 8, 2024 at 8:48 AM Junio C Hamano <gitster@pobox.com> wrote:

merge-ll is wildly different than every other *-ll.h file we have in the tree; the latter set of files may be misnamed, for reasons other than what you are suggesting here. hash-ll, hex-ll, etc. exist due to the main include file having some rarely used API that require more #include statements, and most users of e.g. hex functions can get away with just including hex-ll.h rather than the full hex.h. Thus, hex-ll.h is _not_ "low level details that you can skip", but "the _primary_ data structures and functions". It doesn't get the name hex.h, though, because if we did that then the folks that need both primary parts of the API and the occasional additional function would need to have two hex-related includes. Also, every function declared within hex-ll.h is still defined within hex.c; there is no separate hex-ll.c file, and the same is true of all the other *-ll.h files other than merge-ll.h. As such, there is absolutely no relation between hex-ll.h, hash-ll.h, fsmonitor-ll.h, etc. Using an ll- prefix on those filenames thus makes no sense to me. (It's not clear that -ll even makes sense as a suffix for these files either, but it's not clear what else to use instead. If I recall correctly I originally put forward "-basics" as a possible name suffix for these files, but someone else suggested "-ll", and not having any better ideas or strong opinions I just went with it.)

merge-ll is different in that it is actually a separate level of the API, and there are both a merge-ll.h file and a merge-ll.c file.

I originally had proposed only adding the hex-ll.h, hash-ll.h, fsmonitor-ll.h, etc. files, but you suggested that ll-merge should either be renamed or that these new files should be (https://lore.kernel.org/git/CABPp-BErrVUnuDjL73edDpmkKUvs6Ny6cYwvueXw1toB4JcF-Q@mail.gmail.com/).

Now, all that said, and assuming we were to go back to a world where the other *-ll.h files don't exist (or are renamed independently with a different suffix), I'm still not understanding why ll-merge makes more sense to you and Phillip than merge-ll. Could you explain more? If you're only interested in the upper-level API functions, that suggests you are already at the function level and looking within a given file. The low-level functions are already split out into a separate file, so you just don't go looking at that separate file. However, if you're interested in "where in this codebase do I find the stuff related to merging", then you aren't in a file but in a directory listing. The first usecase gains no benefit from renaming these files back to ll-merge.[ch], while the other usecase would have been much improved in my experience from being named merge-ll.[ch]. Granted, it's a really minor point, which was why I never brought it up until you suggested making all the other *-ll.h files and ll-merge.[ch] consistent; since renaming the other *-ll.h files made no sense at all to me, I went with renaming ll-merge.[ch] to merge-ll.[ch].

There's probably some other angle to this that you two are viewing this from that just isn't apparent to me. Sorry for not seeing it (yet). Hopefully the above context is at least helpful, though.