[VHDL2019 Feature Request] Reference Port elements in a port declaration

[richardhead]

I was previously instructed to request VHDL features one per post, so here we go. Im looking for the initial quality of life features of VHDL 2019 and I only care about support in synthesis.

Please implement the ability for ports to read other ports in a port declaration.

eg:

entity my_awesome_VHDL2019_entity is
  port (
    s1 : in std_logic_vector(9000 downto 0);
    s2 : s1'subtype
  );
end entity;