Fix version typos.

doc/Language/control.pod6

@@ -154,7 +154,7 @@ start { sleep 1; say "done" }
 say "working";
 # working, done
 
-Note that you need a space between the C<start> and the block. In the example above, the C<start> block is in sink context, since it's not assigned to a variable. From version 6.3, these kind of blocks have an exception handler attached:
+Note that you need a space between the C<start> and the block. In the example above, the C<start> block is in sink context, since it's not assigned to a variable. From version 6.d, these kind of blocks have an exception handler attached:
 
 =for code :skip-test<Illustrates exception>
 start { die "We're dead"; }

doc/Language/variables.pod6

@@ -1098,7 +1098,7 @@ These can also be accessed by the shortcuts C<$0>, C<$1>, C<$2>, etc.
     say $0; # OUTPUT: «｢bbbbb｣␤»
     say $1; # OUTPUT: «｢dddddeff｣␤»
 
-To get all of the positional attributes, you can use C<$/.list> or C<@$/>. Before 6.3, you can also use the C<@()> shortcut (no spaces inside the
+To get all of the positional attributes, you can use C<$/.list> or C<@$/>. Before 6.d, you can also use the C<@()> shortcut (no spaces inside the
 parentheses).
 
     say @$/.join; # OUTPUT: «bbbbbdddddeff␤»