embark-target-file-at-point not properly recognizing filenames?

[slayer152]

embark-act on, say, abcd.txt, in a regular buffer does not recognize file as a target. It looks like embark-target-file-at-point relies first on ffap-file-at-point (which returns nil in the example) and uses (thing-at-point 'filename) only if ffap-file-at-point is non-nil.

I also don't understand the reference to ffap-el-mode in this function but should embark-target-file-at-point also be looking at (thing-at-point 'filename) if ffap-file-at-point returns nil ?

[oantolin]

Let's start with the basics: in your example, are you sure there exists a file called abcd.txt in the current directory? Does the command M-x ffap find it?

[slayer152]

Sorry, I should have described the case better.

abcd.txt doesn't exist in the current directory. My use-case is actually detecting a file at point in a regular buffer even if the file is in a different directory, e.g. files in pre-processor directives like #include <filename>.

On second thought, I guess this detection wouldn't make much sense as most of the actions on files in the embark-file-map won't work if the full file location is not known when embark-act is called. I think it may be better if I detect this as a new target in my config.

Sorry for the trouble - please close this if you agree or I can close this too.

[oantolin]

If ffap can figure out what file is meant, then Embark will target that. I just tried #include <stdio.h> and Embark correctly targeted /usr/include/stdio.h (I actually used Embark to copy that path to the clipboard) despite the default-directory for my file being something under $HOME.

So, I'm guessing that in your situation that M-x ffap isn't finding the file either, is it? How do you use that C file? Do you compile it specifying an include path? Instead of adding your own Embark target you might want to configure ffap to find the correct file instead: just add the directories to user option ffap-c-path.

[oantolin]

Also, let me briefly explain the logic of the file target finder:

• In a dired buffer, it uses dired functions to get the file on the current line.
• In any other case it will target whatever file ffap guesses, namely (ffap-file-at-point), if any. In some cases, even though ffap returns something it still won't target that file (or "file" sometimes):
  1. If ffap returns an http or https URL, then the target is abandoned (left for the url target finder).
  2. If the file at point is an Emacs Lisp library (this is what is tested for with ffap-el-mode), then the target is abandoned (left for the library target finder).

The reason Embark uses (ffap-file-at-point) rather than (thing-at-point 'filename) is that the latter is really just syntactical so whenever point is on a letter, for example, it returns something. The vast majority of the time those "filenames" don't correspond to any file.

[slayer152]

So, I'm guessing that in your situation that M-x ffap isn't finding the file either, is it? How do you use that C file? Do you compile it specifying an include path? Instead of adding your own Embark target you might want to configure ffap to find the correct file instead: just add the directories to user option ffap-c-path.

Yes, M-x ffap doesn't find it. Not C files; the files are in an in-house language and are generated by various flows that can put them in one of ten/hundred directories inside a project. Something like files x, y... generate <filename> which is #include'd in file z. The build flow puts the path of <filename> in another file a1 and a1 is passed to the compiler to compile z.

I'm not sure if I want to look at configuring ffap-c-path because there can be hundreds of #include <filename> in each file and the files are distributed over several directories (even the a1-like files containing filepaths are put in several directories).

So, I'm thinking one of these two:

• With <filename> at point -> consult-find -> M-n/future history -> embark-act -> my/function with completion-candidate as the file target. OR,
• Defining my own target and starting with embark-act

Option 1 is easier/supported out-of-the-box but I'm training my muscle memory to instinctively use embark-act as the front/initial command AMAP. I didn't get the hang of Embark initially but @karthink's post with the gifs was the 'Aha!' moment for me (I'm more of a visual learner). Thank you for this package!

[oantolin]

Oh, I see. Then making your own target that searches for the file sounds like a good option.

And since these aren't C files as I thought then modifying ffap-c-path wouldn't be appropriate, but you could still configure ffap to work for the in-house language, you just need to add an entry to ffap-alist associating the in-house language files with a function that given the base filename figures out the full path. Configuring ffap this way would be an alternative to making an embark target. I think it should be about the same amount of work either way.