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There's been a lot of work on contrib syntax highlighting plugins. One should be picked and added to ikiwiki core.

Ideally, it should support both converting whole source files into wiki pages, as well as doing syntax highlighting as a preprocessor directive (which is either passed the text, or reads it from a file).

The big list of possibilities

  • [[plugins/contrib/highlightcode]] uses [[cpan Syntax::Highlight::Engine::Kate]], operates on whole source files only, has a few bugs (see here, and needs to be updated to support [[bugs/multiple_pages_with_same_name]].
  • [[cpan IkiWiki-Plugin-syntax]] only operates as a directive. Interestingly, it supports multiple highlighting backends, including Kate and Vim.
  • [[plugins/contrib/syntax]] only operates as a directive ([[not_on_source_code_files|automatic_use_of_syntax_plugin_on_source_code_files]]), and uses [[cpan Text::VimColor]].
  • [[plugins/contrib/sourcehighlight]] uses src-highlight, and operates on whole source files only. Needs to be updated to support [[bugs/multiple_pages_with_same_name]].
  • [[sourcecode|todo/automatic_use_of_syntax_plugin_on_source_code_files/discussion]] also uses src-highlight, and operates on whole source files. Updated to work with the fix for [[bugs/multiple_pages_with_same_name]]. Untested with files with no extension, e.g. Makefile.

General problems

  • Using non-perl syntax highlighting backends is slow. I'd prefer either using a perl module, or a multiple-backend solution that can use a perl module as one option. (Or, if there's a great highlighter python module, we could use an external plugin..)

  • Currently no single plugin supports both modes of operation (directive and whole source file to page).

    This is now fixed by the [[ikiwiki/directive/format]] directive for all whole-source-file plugins, right?

  • Nothing seems to support [[wiki-formatted_comments|wiki-formatted_comments_with_syntax_plugin]] inside source files. Doing this probably means post-processing the results of the highlighting engine, to find places where it's highlighted comments, and then running them through the ikiwiki rendering pipeline. This seems fairly doable with [[cpan Syntax::Highlight::Engine::Kate]], at least.

  • The whole-file plugins tend to have a problem that things that look like wikilinks in the source code get munged into links by ikiwiki, which can have confusing results. Similar problem with preprocessor directives. One approach that's also been requested for eg, [[plugins/contrib/mediawiki]] is to allow controlling which linkification types a page type can have on it.

    The previous two points seem to be related. One thought: instead of getting the source from the content parameter, the plugin could re-load the page source. That would stop directives/links from being processed in the source. As noted above, comments could then be parsed for directives/links later.

    Would it be worth adding a nodirectives option when registering an htmlize hook that switches off directive and link processing before generating the html for a page?

  • The whole-file plugins all get confused if there is a foo.c and a foo.h. This is trivially fixable now by passing the keepextension option when registering the htmlize hooks, though.

  • Whole-file plugins register a bunch of htmlize hooks. The wacky thing about it is that, when creating a new page, you can then pick "c" or "h" or "pl" etc from the dropdown that normally has "mdwn" etc in it. Is this a bug, or a feature? (Even if a feature, plugins with many extensions make the dropdown unusable.. One way to deal with that is have a config setting that lists what extensions to offer highlighting for. Most people won't need/want the dozens some engines support.)

  • The per page highlighters can't handle creating wiki pages from "Makefile", or other files without a significant extension. Not clear how to fix this, as ikiwiki is very oriented toward file extensions. The workaround is to use a directive on a wiki page, pulling in the Makefile.

    I wonder how hard it would be to make a patch whereby a file with no . in the name, and a name that matches a filetype, and where that filetype was registered keepextension, then the file is just chosen as the appropriate type. This would allow Makefile to work.

like this:

diff --git a/IkiWiki.pm b/IkiWiki.pm
index 8d728c9..1bd46a9 100644
--- a/IkiWiki.pm
+++ b/IkiWiki.pm
@@ -618,6 +618,8 @@ sub pagetype ($) { #{{{
 	
 	if ($page =~ /\.([^.]+)$/) {
 		return $1 if exists $hooks{htmlize}{$1};
+	} elsif ($hooks{htmlize}{$page}{keepextension}) {
+		return $page;
 	}
 	return;
 } #}}}

format directive

Rather than making syntax highlight plugins have to provide a preprocessor directive as well as handling whole source files, perhaps a generic format directive could be used:

\[[!format pl """..."""]]

That would run the text through the pl htmlizer, from the syntax hightligh plugin. OTOH, if "rst" were given, it would run the text through the rst htmlizer. So, more generic, allows mixing different types of markup on one page, as well as syntax highlighting. Does require specifying the type of format, instead of allowing it to be guessed (which some syntax highlighters can do). (This directive is now implemented..)

Hmm, this would also allow comments inside source files to have mdwn embedded in them, without making the use of mdwn a special case, or needing to postprocess the syntax highlighter output to find comments.

/* \[[!format mdwn """

This is a comment in my C file. You can use mdwn in here.

"""]] */

Note that this assumes that directives are expanded in source files.