Prolog filetype problem

[Gautier DI FOLCO]

Hi all,

I write some code in Prolog and some code in Perl, the problem is that these
two languages have the same extension, is their a mean to set the good
filetype not according to their extension, but according to the language
highlighting that find the most tokens?

For your help,
In advance,
Thanks.

[Ben Fritz]

On Sunday, September 30, 2012 4:07:41 PM UTC-5, Gautier DI FOLCO wrote:
> Hi all,
>
> I write some code in Prolog and some code in Perl, the problem is that these
> two languages have the same extension, is their a mean to set the good
> filetype not according to their extension, but according to the language
>
> highlighting that find the most tokens?
>

It looks like Vim will automatically detect prolog rather than Perl if the first non-blank line contains any of:

1. the word "prolog"
2. a prolog comment, % or /* ... */
3. the prolog :- construct

Otherwise, Vim detects Perl. So for existing files, just get into the habit of starting the file with a header comment and you'll be fine.

I guess new files will always detect as Perl, but there's really not any way I can think of for Vim to detect in a general way what filetype a brand-new empty file should be. You could set up some BufNewFile autocmds based on project directory or something if you like for this.

[Gautier DI FOLCO]

2012/9/30 Ben Fritz <fritzo...@gmail.com>

It looks like Vim will automatically detect prolog rather than Perl if the first non-blank line contains any of:

1. the word "prolog"
2. a prolog comment, % or /* ... */
3. the prolog :- construct

Otherwise, Vim detects Perl. So for existing files, just get into the habit of starting the file with a header comment and you'll be fine.

I guess new files will always detect as Perl, but there's really not any way I can think of for Vim to detect in a general way what filetype a brand-new empty file should be. You could set up some BufNewFile autocmds based on project directory or something if you like for this.

Clever, thank you.

[Eric Marceau]

On my system (Ubuntu MATE 20.04) there is no default file /etc/magic (per the man for "file").

My local definitions were placed in that file which are interpreted before other system definitions.

The content of my "/etc/magic" file is as follows:

# Magic local data for file(1) command.
# Insert here your local magic data. Format is described in magic(5).
0    string    %%Prolog    Prolog Predicate File (Non-Specific)

0    string    %%gprolog    Prolog Predicate File (GNU Prolog)

0    string    %%swipl        Prolog Predicate File (SWI-Prolog)

0    string    %%yap        Prolog Predicate File (YAP Prolog)

0    string    %%eclipse    Prolog Predicate File (ECLiPSe)

0    string    %%bprolog    Prolog Predicate File (B-Prolog)

0    string    %%poplog    Prolog Predicate File (Poplog)

0    string    %%lpaprolog    Prolog Predicate File (LPA Prolog)

0    string    %%isoprolog    Prolog Predicate File (ISO-Compliant Prolog)

0    string    [Pp][Rr][Oo][Ll][Oo][Gg]    Prolog Predicate File (ISO-Compliant Prolog)

0    search    :-    Prolog Predicate File (Non-Specific :-)

0    search    -->    Prolog Predicate File (Non-Specific -->)
#
#0    search/2048    [Pp][Rr][Oo][Ll][Oo][Gg]    Prolog Predicate File (ISO-Compliant Prolog)
#
#0    string    %     Prolog Predicate File (Non-Specific %)
#
#

As can be seen, I was attempting to specify definitions which would identify the various dialects of Prolog and have "file" report those.  Works splendidly for me!

[Doug Kearns]

On Mon, 1 Oct 2012 at 07:32, Ben Fritz <fritzo...@gmail.com> wrote:

<snip>

> Otherwise, Vim detects Perl. So for existing files, just get into the habit of starting the file with a header comment and you'll be fine.
>
> I guess new files will always detect as Perl, but there's really not any way I can think of for Vim to detect in a general way what filetype a brand-new empty file should be. You could set up some BufNewFile autocmds based on project directory or something if you like for this.

Setting g:filetype_pl might be helpful here. You could even just
manually set it if you were having a Prolog-only day for example. See
:help filetype-overrule

Regards,
Doug