--- /dev/null
+use strict;
+use warnings;
+use Unicode::Normalize qw( NFKD );
+use Text::Unidecode qw( unidecode );
+
+our %rows;
+my %g; # present group classes
+{
+ rows => [0, 1],
+ def => {
+ '' => {
+ map {
+ my $v = $rows{$_};
+ my $class = (
+ !defined $v || $_ eq $v ? 1 # identical
+ : $v =~ /\A\p{Mn}+\z/ ? 9 # combining accent
+ : $v =~ /\A[\p{Sk}\p{Lm}]+\z/ ? 8 # modifier symbol
+ : $v =~ /\A[\pM\pP]+\z/ ? 7 # mark
+ : NFKD($v) =~ /\Q$_/ ? 2 # decomposed equivalent
+ : unidecode($v) =~ /\Q$_\E+/i ? 4 # transliterated
+ : $v =~ /^\p{Latin}/ ? 5 # latin script
+ : 6
+ );
+ $g{$class} = 1;
+ $_ => "g$class"
+ } keys %rows
+ },
+ },
+ key => \%rows,
+ flag => {
+ g1 => ['unaltered', "same results as without modifier"],
+ g2 => ['accented', "decomposes to the original letter with a combining accent"],
+ g4 => ['similar', "transliterates (mostly) into the unmodified letter"],
+ g5 => ['latin', "a different (accented) latin letter"],
+ g6 => ['symbol', "other character not directly deducible from key"],
+ g7 => ['punctuation', "(punctuation) mark"],
+ !$g{9} ? () : (
+ g8 => ['mark', "modifier letter or mark (spacing diacritic)"],
+ g9 => ['combining', "diacritical mark to be combined with a following character"],
+ ),
+ },
+}