+my %versions;
+if (my ($somerow) = values %{ $caniuse->{data} }) {
+ while (my ($browser, $row) = each %{ $somerow->{stats} }) {
+ $versions{$browser} = [ sort { paddedver($a) cmp paddedver($b) } keys %$row ];
+ }
+}
+my @browsers = grep { $versions{$_} }
+ qw(trident gecko webkit_saf ios_saf webkit_chr android presto op_mob op_mini);
+
+print <<'';
+<p id="intro">Alternate rendition of Fyrd's <a href="http://caniuse.com/">when can I use...</a> page
+
+my ($canihas, $usage);
+given ($get{usage} // 'wm') {
+ when (!$_) {
+ # none
+ }
+ when (!/^\w+$/) {
+ printf "<p>Invalid browser usage data request: <em>%s</em>",
+ 'identifier must be alphanumeric name or <q>0</q>';
+ }
+ $canihas = do "browser-usage-$_.inc.pl" or do {
+ printf "<p>Browser usage data not found: <em>%s</em>", $! || $@;
+ break;
+ };
+ $usage = $_;
+ my $ref = $canihas->{-source} || 'unknown';
+ $ref = sprintf '<a href="%s">%s</a>', $_, $ref for $canihas->{-url} || ();
+ $ref .= " $_" for $canihas->{-date} || ();
+ print "\nwith $ref browser usage statistics";
+}
+:>.
+</p>
+
+<:
+$canihas ||= {
+ map {
+ $_ => +{
+ map {
+ my $zero = $#$_ - 2; # baseline index
+ ($_->[$zero - 2] => .5), # past
+ ($_->[$zero - 1] => 10 ), # previous
+ ($_->[$zero + 2] => 0 ), # future
+ ($_->[$zero + 1] => .5), # next
+ ($_->[$zero ] => 30 ), # current
+ } $caniuse->{agents}->{$_}->{versions}
+ }
+ } @browsers
+}; # fallback hash based on release semantics
+my $scorediv = (max(map { ref $_ eq 'HASH' && sum(values %$_) } values %$canihas) // 1) / 100;
+
+print '<table class="mapped">';
+print '<col span="3">'; # should match first thead row
+printf '<colgroup span="%d">', scalar @{ $versions{$_} } for @browsers;
+say '</colgroup><col>';
+
+my $header = join('',
+ '<tr>',
+ '<th colspan="3">feature',
+ (map {
+ my $name = $caniuse->{agents}->{$_}->{browser};
+ sprintf('<th colspan="%d" class="%s" title="%s">%s',
+ scalar @{ $versions{$_} },
+ join(' ', map {"b-a-$_"} grep {$_}
+ $_, @{ $caniuse->{agents}->{$_} }{'prefix', 'type'},
+ ),
+ join(' ',
+ sprintf('%.1f%%', sum(values %{ $canihas->{$_} })),
+ $name,
+ ),
+ do {
+ length $name < 3 + @{ $versions{$_} }*2 ? $name
+ : $caniuse->{agents}->{$_}->{abbr};
+ },
+ )
+ } @browsers),
+ '<th>%',
+);
+print '<thead>', $header;
+# preceding row without any colspan to work around gecko bug
+print "\n<tr>";
+print '<td>' x 3;
+for my $browser (@browsers) {
+ printf('<td title="%s"%s>%s',
+ join(' ',
+ sprintf('%.1f%%', $canihas->{$browser}->{$_}),
+ "version $_",
+ ),
+ (map {
+ defined $_ && !$_ && ' class="ex"'
+ } $caniuse->{agents}->{$browser}->{verrelease}->{$_}),
+ showversions($_),
+ ) for @{ $versions{$browser} };
+}
+print '<td>' x 1;
+say '</thead>';
+say '<tfoot>', $header, '</tfoot>';
+
+sub featurescore {
+ # relative amount of support for given feature
+ state $statspts = { y=>10, 'y x'=>10, a=>5, 'a x'=>5, j=>2, 'p j'=>2, 'p p'=>2, p=>1 };
+ my $rank = 0;
+ if (my $row = shift) {
+ if ($canihas) {
+ while (my ($browser, $versions) = each %$row) {
+ ref $versions eq 'HASH' or next;
+ while (my ($version, $_) = each %$versions) {
+ $rank += ($canihas->{$browser}->{$version} || .001) * $statspts->{$_};
+ }
+ }
+ return $rank;
+ }
+
+ while (my ($browser, $vercols) = each %versions) {
+ my $div = 0; # multiplier exponent (decreased to lower value)
+ my @vers = map { $row->{$browser}->{$_} } @$vercols;
+ if (my $current = $caniuse->{agents}->{$browser}->{versions}->[-3]) {
+ my @future; # find upcoming releases (after current)
+ for (reverse @$vercols) {
+ last if $_ eq $current;
+ push @future, pop @vers;
+ $_ eq 'u' and $_ = $vers[-1] for $future[-1]; # inherit latest value if unknown
+ }
+ splice @vers, -1, 0, @future; # move ahead to decrease precedence
+ }
+ $rank += $statspts->{$_} * 2**($div--) for reverse @vers;
+ }
+ }
+ return $rank;
+}