Re: [Maxima-discuss] file_search behavior?

[Raymond T. <toy...@gm...>]

On Thu, Jul 21, 2022 at 10:58 AM Robert Dodier <rob...@gm...>
wrote:

> On Wed, Jul 20, 2022 at 1:34 PM Raymond Toy <toy...@gm...> wrote:
>
> >> So if the file actually exists in the current working directory, the
> >> path list isn't referenced.
>
> > But this can easily be achieved by setting file_search_lisp and
> file_search_maxima with the current directory at the beginning.
> >
> > Leaving it as is makes it impossible to make force maxima not to load
> file from the current dir.
>
> Yeah, I can see that being able to disallow the  current directory is
> a useful behavior. However, I wonder if we're going to bump into
> problems trying to implement that. Common Lisp has a notion of
> pathname defaults which is distinct from the current working directory
> -- as long as we're using PROBE-FILE to assess whether some would-be
> path exists, there is potential for unexpected results.
>

IIRC, the pathname defaults usually default to the current directory, but
it can be changed.

Since there's precedence on this, and it's how maxima has worked since
forever (even if we can fake it), I think I'm going to leave it.

>
> Maybe I'm worrying too much. I guess that an actual implementation
> isn't hard, so we can just try it and find out.
>
> > This is unlike any other search path for any programs I know of.
>
> Well, I dunno. I looked at some programs I often use, and there's a
> variety of behaviors.
>
>  * Matlab: current working directory is not on path list, but Matlab
> finds files in cwd anyway
>  * Octave: cwd is on path list, and user cannot remove it (attempt
> evokes error message)
>  * R: source("foo.R") only looks for foo.R in specified path, or cwd
> if no leading path; thereafter complicated behavior depending on
> optional argument chdir
>
> I know that sh, bash, probably other shells, only look for executables
> in cwd if given explicit path ./foo, or if . is on PATH. What are
> other programs which act like that?
>
> best,
>
> Robert
>


-- 
Ray