error in fixed point division

ibrary IEEE;

use IEEE.STD_LOGIC_1164.ALL;

use IEEE.NUMERIC_STD.ALL;

library ieee_proposed;

use ieee_proposed.fixed_float_types.all;

use ieee_proposed.fixed_pkg.all;

entity div_fixed is

Port ( c : out ufixed(6 downto -10));

end div_fixed;

architecture Behavioral of div_fixed is

signal a :ufixed(6 downto-7);

signal l:ufixed(2 downto 0);

signal k: ufixed(6 downto -10);

begin

a<= to_ufixed(12.56,6,-7);

l<= to_ufixed(4,2,0);

k<=(a/l);<-------- error.

c<=k;

end Behavioral;

error is : Line 46. / can not have such operands in this context.

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