library ieee;
use ieee.std_logic_1164.all;

entity ent2 is
  generic (
    TUSER_WIDTH : natural := 1);
end ent2;

architecture ent of ent2 is
  type data_t is record
    tuser : std_logic_vector;
  end record;

  type data_array_t is array (natural range <>) of data_t;
  type std_logic_array_t is array (natural range <>) of std_logic_vector;
  subtype tuser_array_t is std_logic_array_t(open)(TUSER_WIDTH - 1 downto 0);

begin

  process
    procedure write_data (constant tuser : tuser_array_t) is
    begin
      for i in tuser'range loop
        report integer'image(i) & " =>" & to_bstring(tuser(i));
      end loop;

      assert tuser(1)(0) = '1'; -- <<<<<====== This should not fail
    end procedure;

    procedure handle_data_array ( constant data : data_array_t) is
      variable local_tuser : std_logic_array_t(data'range)(TUSER_WIDTH - 1 downto 0);
    begin
      -- Convert a list of tuples into two lists
      for i in data'range loop
        local_tuser(i) := data(i).tuser;
        assert local_tuser(i) = data(i).tuser
          report "local_tuser and data(i).tuser should not be different here";
      end loop;

      write_data(tuser => local_tuser);
    end;

    constant data : data_array_t(0 to 1)(tuser(0 downto 0)) :=
      (0 => (tuser => (0 downto 0 => '0')),
       1 => (tuser => (0 downto 0 => '1')));
  begin
    handle_data_array(data);
    wait;
  end process;
end ent;