digraphs: smart deprecation of xorg alternates

[sheet.git] / digraphs.plp

diff --git a/digraphs.plp b/digraphs.plp
index b40eac0915cefd19f0176e4bbed836f7f4da169d..718915dab4ed935c213ddefd96709ebf5bec7d2c 100644 (file)
--- a/digraphs.plp
+++ b/digraphs.plp
@@ -1,4 +1,5 @@
 <(common.inc.plp)><:
+use 5.010;  # state
 
 Html({
        title => 'digraph cheat sheet',
@@ -7,7 +8,8 @@ Html({
                "Complete table of digraph characters from RFC-1345.",
        ],
        keywords => [qw'
-               digraph compose character char glyph table unicode vim
+               digraph mnemonic compose composition pair
+               character char glyph table unicode vim
        '],
        stylesheet => [qw'light'],
        data => [qw( digraphs.inc.pl )],
@@ -16,8 +18,12 @@ Html({
 :>
 <h1>RFC-1345 Digraphs</h1>
 
-<p>i^k in <a href="/vi">Vim</a>.
-Also see <a href="/unicode">common digraphs</a>.</p>
+<p>Character mnemonics
+following composition key ⎄:
+i^k in <a href="/vi">Vim</a>,
+^u^\ in <a href="/readline">Emacs</a>,
+^a^v in <a href="/screen">Screen</a>.
+Also see <a href="/unicode">common Unicode</a>.</p>
 
 <p class="aside">Unofficial <span class="u-prop ex">proposals</span>
 are available as <a href="/digraphs.vim">ex commands</a>.</p>
@@ -40,9 +46,29 @@ if (exists $get{xorg}) {
        my $xorg = do 'data/digraphs-xorg.inc.pl'
                or die "Error loading Xorg data: ", $@ // $!;
        $_ = [ord $_] for values %{$xorg};
-       $xorg->{$_}->[2] =  # class = same as rfc | any other spec | xorg only
-               $di->{$_} ? $di->{$_}->[2] =~ /\bu-di\b/ ? 'l5' : 'l3' : 'l1'
+       $xorg->{$_}->[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;