mktables: Fix Useless use of const in void context

The code was attempting to get a slice of an entire array excluding the
0th element.  But it was using the wrong incantation.

The array is the path to a file with each element being one directory.

And it just happened to work because of the current layout of the
directories.

This commit moves this slice fetch so it is not done in the loop, adds
another sanity check, and is generally clearer what is going on.

Author: khwilliamson

charclass_invlists.inc

@@ -456712,7 +456712,7 @@ static const U8 WB_dfa_table[] = {
  * 4be1c18e7b121d951018065b453bb05083f624c8f905ce8be7c0f354c9097c95 lib/unicore/extracted/DLineBreak.txt
  * 786833e0a3f5ec0c0cd0940e4c15f730f3a92163f354ecd7dede28a70c0fa892 lib/unicore/extracted/DNumType.txt
  * 00b43cc5c9b86a834f82389c4537f103e652821387daa556f0bd220f6c23007e lib/unicore/extracted/DNumValues.txt
- * 53e3072f38ef578e901c0f6d47e42d8b2d596fef60a4fce3a605c6c14be51faf lib/unicore/mktables
+ * 927f970f471272a402927086bc5f013b831e5ed063c453511f1696c404d06415 lib/unicore/mktables
  * 63f771c327e92574fbd77919586079c38f669058a5e6b67ccec385ef8fcde882 lib/unicore/version
  * 0a6b5ab33bb1026531f816efe81aea1a8ffcd34a27cbea37dd6a70a63d73c844 regen/charset_translations.pl
  * c7ff8e0d207d3538c7feb4a1a152b159e5e902d20293b303569ea8323e84633e regen/mk_PL_charclass.pl

lib/unicore/mktables

@@ -16072,9 +16072,18 @@ sub register_file_for_name($table, $directory_ref, $file) {
 
     # All go in the same subdirectory of unicore, or the special
     # pseudo-directory '#'
-    if ($directory_ref->[0] !~ / ^ $matches_directory | \# $ /x) {
+    my $sub_directory;
+    if ($directory_ref->[0] eq '#') {
+        Carp::my_carp("Pseudo-directory '#' should be only directory "
+                .  join('/', @{$directory_ref}, $file))
+                                                    if $directory_ref->@* > 1;
+        $sub_directory = '#';
+    }
+    else {
         Carp::my_carp("Unexpected directory in "
-                .  join('/', @{$directory_ref}, $file));
+                .  join('/', @{$directory_ref}, $file))
+                                if $directory_ref->[0] ne $matches_directory;
+        $sub_directory = join '/', $directory_ref->@[1 .. $#$directory_ref];
     }
 
     # For this table and all its equivalents ...
@@ -16086,7 +16095,7 @@ sub register_file_for_name($table, $directory_ref, $file) {
         # No swash means don't do the rest of this.
         next if $table->isa('Map_Table') && $table->fate != $ORDINARY;
 
-        my $sub_filename = join('/', $directory_ref->[1, -1], $file);
+        my $sub_filename = "$sub_directory/$file";
 
         my $property = $table->property;
         my $property_name = ($property == $perl)

lib/unicore/uni_keywords.pl

@@ -79,7 +79,7 @@
  * 4be1c18e7b121d951018065b453bb05083f624c8f905ce8be7c0f354c9097c95 lib/unicore/extracted/DLineBreak.txt
  * 786833e0a3f5ec0c0cd0940e4c15f730f3a92163f354ecd7dede28a70c0fa892 lib/unicore/extracted/DNumType.txt
  * 00b43cc5c9b86a834f82389c4537f103e652821387daa556f0bd220f6c23007e lib/unicore/extracted/DNumValues.txt
- * 53e3072f38ef578e901c0f6d47e42d8b2d596fef60a4fce3a605c6c14be51faf lib/unicore/mktables
+ * 927f970f471272a402927086bc5f013b831e5ed063c453511f1696c404d06415 lib/unicore/mktables
  * 63f771c327e92574fbd77919586079c38f669058a5e6b67ccec385ef8fcde882 lib/unicore/version
  * 0a6b5ab33bb1026531f816efe81aea1a8ffcd34a27cbea37dd6a70a63d73c844 regen/charset_translations.pl
  * c7ff8e0d207d3538c7feb4a1a152b159e5e902d20293b303569ea8323e84633e regen/mk_PL_charclass.pl