Identifier "UNSIGNED" is not directly visible

Question

i have used the following libaries

LIBRARY IEEE;

USE ieee.std_logic_1164.all;

USE ieee.std_logic_arith.all;

USE ieee.numeric_std.all;

still the error in modelsim shows :

** Error: G:/vhdl code/vhdl code/dwt_main.vhd(30): (vcom-1078) Identifier "UNSIGNED" is not directly visible.

Potentially visible declarations are:

ieee.NUMERIC_STD.UNSIGNED (subtype declaration)

ieee.std_logic_arith.UNSIGNED (type declaration)

** Error: G:/vhdl code/vhdl code/dwt_main.vhd(31): (vcom-1078) Identifier "SIGNED" is not directly visible.

Potentially visible declarations are:

ieee.NUMERIC_STD.SIGNED (subtype declaration)

ieee.std_logic_arith.SIGNED (type declaration)

how to solve it

altera_forum · Answer

Curious, what did you write for dwt_main.vhd line 30 and 31?

altera_forum · Answer

line 30    TYPE buf_ary IS ARRAY(NATURAL RANGE &lt;&gt;) OF UNSIGNED(7 DOWNTO 0); line 31     TYPE buf_ary_d IS  ARRAY (NATURAL RANGE &lt;&gt;) OF SIGNED(7 DOWNTO 0);

altera_forum · Answer

Try leaving out: USE ieee.std_logic_arith.all;
 It is a deprecated library, you will find everything you need in: USE ieee.numeric_std.all;

altera_forum · Answer

i have already included these libraries above  i have used the following libaries   LIBRARY IEEE; USE ieee.std_logic_1164.all; USE ieee.std_logic_arith.all; USE ieee.numeric_std.all;

altera_forum · Answer

Try just the following:  library ieee ; use ieee.std_logic_1164.all ; use iee.numeric_std.all;

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Identifier "UNSIGNED" is not directly visible

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