web commit by PaulWise: add headinganchors plugin

doc/plugins/contrib/headinganchors.mdwn

@@ -0,0 +1,33 @@
+This is a simple plugin to add ids to all headings, based on their text. It works as a postprocessing filter, allowing it to work on mdwn, wiki, html, rst and any other format that produces html. The code is available here:
+
+	#!/usr/bin/perl
+	# quick HTML heading id adder by Paul Wise
+	package IkiWiki::Plugin::headinganchors;
+
+	use warnings;
+	use strict;
+	use IkiWiki 2.00;
+
+	sub import { #{{{
+	        hook(type => "sanitize", id => "headinganchors", call => \&headinganchors);
+	} # }}}
+
+	sub text_to_anchor {
+	        my $str = shift;
+	        $str =~ s/^\s+//;
+	        $str =~ s/\s+$//;
+	        $str = lc($str);
+	        $str =~ s/[&\?"\'\.,\(\)!]//mig;
+	        $str =~ s/[^a-z]/_/mig;
+	        return $str;
+	}
+
+	sub headinganchors (@) { #{{{
+	        my %params=@_;
+	        my $content=$params{content};
+	        $content=~s{<h([0-9])>([^>]*)</h([0-9])>}{'<h'.$1.' id="'.text_to_anchor($2).'">'.$2.'</h'.$3.'>'}gie;
+	        #$content=~s/(<img(?:\s+(?:class|id|width|height)\s*="?\w+"?)*)\s+src=\s*"\/([^"]*)"/$1 src="$baseurl$2"/mig;
+	        return $content;
+	} # }}}
+
+	1