Source of digraphs.plp

<(common.inc.plp)><:
use 5.010;  # state

my $mode = ($ENV{PATH_INFO} // '') eq '/xorg' || exists $get{xorg};
my $modename = $mode ? 'X.Org' : 'RFC-1345';

Html({
	title => 'digraph cheat sheet',
	version => '1.2',
	description => [
		"Complete table of digraph characters from $modename.",
	],
	keywords => [qw'
		digraph mnemonic compose composition pair
		character char glyph table unicode vim xorg x11 x
	'],
	stylesheet => [qw'light'],
	data => [qw( digraphs.inc.pl )],
});

:>
<h1><:= $modename :> Digraphs</h1>

<p>Character mnemonics following compose key ⎄<:
say join("\n",
	$mode ? (
		' in the X Window System (Shift+AltGr by default).',
		'Differences from <a href="/digraphs">RFC-1345</a> are indicated.',
	) : (':',
		'i^k in <a href="/vi">Vim</a>,',
		'^u^\ in <a href="/readline">Emacs</a>,',
		'^a^v in <a href="/screen">Screen</a>.',
		'Similar but different from <a href="/digraphs/xorg">X.Org</a>.',
	),
	'Also see <a href="/unicode">common Unicode</a>.</p>',
);
say '<p class="aside">Unofficial <span class="u-l2">proposals</span>',
	' are available as <a href="/digraphs.vim">ex commands</a>.' if not $mode;
:>

<:
my $di = do 'digraphs.inc.pl'
	or die "Error loading digraphs data: ", $@ // $!;

if (exists $get{v}) {
	# show characters for inverted mnemonics (vim alternatives)
	$di->{ substr($_, 1, 1) . substr($_, 0, 1) } ||=
		[ $di->{$_}->[0], '', 'l0 ex', '', $di->{$_}->[4] ]
		for grep { ref $di->{$_} } keys %{$di};
}

my @chars = (
	[qw{! " % ' ( ) * + , - . /}],
	['0'..'9'], [qw{: ; < = > ?}],
	['A'..'M'], ['N'..'Z'],
	['a'..'m'], ['n'..'z'],
);
my @chars2 = (['_'], @chars);  # trailing character (extended set)
my @columns = !exists $get{split} ? \@chars2 :
	([@chars2[0, 1, 3, 4, 6]], [@chars2[2, 5, 7]]);

if ($mode) {
	my $xorg = do 'data/digraphs-xorg.inc.pl'
		or die "Error loading Xorg data: ", $@ // $!;
	$_ = [ord $_] for values %{$xorg};
	$xorg->{$_}->[2] = # class = compatibility
		$di->{$_} ? $di->{$_}->[0] != $xorg->{$_}->[0] ? 'l1' :  # conflict
		$di->{$_}->[2] =~ /\bu-di\b/ ? 'l5' : 'l3' : 'l2'  # rfc|any|none
		for keys %{$xorg};

	for my $cp (map {$_->[0]} values %{$xorg}) {
		next if (state $seen = {})->{$cp}++;  # List::MoreUtils::uniq

		# find multiple equivalent mnemonics
		my @equiv = grep {$cp eq $_->[0]}
			map {$xorg->{$_}} sort keys %{$xorg}; # values ordered by mnem.

		# search for the most compatible match
		my ($compat) = sort {
			$equiv[$b]->[2] cmp $equiv[$a]->[2]  # highest level
			|| $b <=> $a  # fallback to last mnemonic
		} 0 .. $#equiv;

		# reclassify all but one as level 0 (omitted)
		splice @equiv, $compat // -1, 1, ();
		$_->[2] = 'l0 ex' for @equiv;
	}

	$chars2[0] = [qw( # ^ _ ` ~ )];
	@chars = @chars2;
	$di = $xorg;
}

for my $colchars (@columns) {
print '<table class="glyphs dimap"><col>';
print qq'<colgroup span="$_">' for map {scalar @$_} @{$colchars};
print "</colgroup><col>\n";
for my $section (qw{thead tfoot}) {
	print "<$section><tr><th>↳";
	print '<th>', EscapeHTML($_) for map {@$_} @{$colchars};
	print "<th>&nbsp;\n";
}
for my $c1group (@chars) {
	print '<tbody>';
	for my $c1 (@$c1group) {
		print '<tr><th>', EscapeHTML($c1);
		for my $c2 (map {@$_} @$colchars) {
			my $mnem = $c1 . $c2;
			if (not defined $di->{$mnem}) {
				print '<td>';
				next;
			}
			if (ref $di->{$mnem} ne 'ARRAY') {
				printf '<td class="X Xr" title="%s">', EscapeHTML($mnem);
				next;
			}
			my ($codepoint, $name, $support, $script, $string) = @{ $di->{$mnem} };

			my $glyph = $string || chr $codepoint;
			utf8::upgrade($glyph);  # prevent latin1 output
			my $desc = $mnem . ($name && " ($name)");
			my @class = ('X', grep {$_} $support && "u-$support", $script);

			$glyph = EscapeHTML($glyph);
			$glyph = "<span>$glyph</span>" if $script =~ /\bZs\b/;

			printf "\n".'<td class="%s" title="%s">%s',
				join(' ', @class), EscapeHTML($desc), $glyph;
		}
		print "\n<th>", EscapeHTML($c1), "\n";
	}
}
print "</table>\n";
print '<hr>' if exists $get{split};
}

if ($mode) {
:>
<div class="legend">
	<table class="glyphs"><tr>
	<td class="X l5">matching RFC-1345
	<td class="X l3">matching proposal
	<td class="X l2">unique to Xorg
	<td class="X l1">conflict
	<td class="X l0 ex">duplicate
	</table>
</div>
<: } else { :>
<div class="legend">
	<table class="glyphs"><tr>
	<td class="X Cc">control
	<td class="X Zs"><span>space</span>
	<td class="X Mn">combining
	<td class="X Sk">spacing&nbsp;modifier
	<td class="X Pf">quote
	<td class="X Po">punctuation
	<td class="X So">symbol
	<td class="X Sm">math
	<td class="X Sc">currency
	<td class="X No">numeric
	<td class="X Greek">greek
	<td class="X Cyrillic">cyrillic
	<td class="X Latin">latin
	<td class="X Hebrew">hebrew
	<td class="X Arabic">arabic
	<td class="X Hangul">korean
	<td class="X Hiragana">japanese
	<td class="X Bopomofo">chinese
	</table>

	<table class="glyphs"><tr>
	<td class="X u-l4">full support
	<td class="X u-l3">vim extension
	<td class="X u-l3 ex">vim v8.0
	<td class="X u-l2">proposal
	<td class="X u-l1">not in vim
	</table>
</div>

<: }