bug#8439: [PATCH] ffap.el -- detect paths with spaces (v2)

[Eli Zaretskii <eliz@gnu.org>]

> Date: Fri, 19 Oct 2012 13:05:56 +0300
> From: jari <jari.aalto@cante.net>
> Cc: 8439@debbugs.gnu.org, hochberg@dmhsoftware.com
> 
> | What will this do to text such as the one below?
> | 
> |  C:\emacs\bin\prog1.exe on Windows or /usr/bin/prog1 on Unix.
> 
> User can enable/disable if spaces are taken into account. If enabled,
> the result is:
> 
>   "C:\emacs\bin\prog1.exe on Windows or /usr/bin/prog1"

Why would it exclude the " on Unix." part?

> If you have strategiy to make it better, please suggest.

(I don't use ffap, so take the below with a grain of salt.)

Several things come to mind:

 . You could modify the heuristics depending on the major mode.  E.g.,
   if it's Text or anything derived from text, file names with spaces
   will generally be delimited by quotes.

 . You could by default stop "skipping" when you see common words like
   "on", "and", "or", "and/or", etc.

 . You could by default stop when the slash flavor changes, like first
   \, then / (see my example).

 . At least in text modes, punctuation (with the notable exception of
   a period) will not normally be part of a file name.

> | >   3. In Cygwin Emacs the paths are expected to be in "/cygdrive/<letter>/"
> | >      format.
> | 
> | What about Posix-standard /foo/bar/baz, which is the usual case on
> | Cygwin?
> 
> Only "<drive letter>:" is converted into "/cygdrive/<drive letter>" under
> Cygwin.

Sorry, I don't follow.  You said "In Cygwin Emacs the paths are
_expected_ to be", so I assumed you mean the file names on Cygwin are
_required_ to be in the /cygdrive/x/foo form.  Maybe I misunderstood
what you meant.