Using VHDL-2008 it becomes even more simple and elegant:
process(all)
begin
if not(A) or not(B) or not(C) then
F <= '0';
elsif .. .
I have found that VHDL 2008 makes code more readable in this way.
Best, James
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method 1(brute force):
process(A,B,C)
begin
if A = '0' and B = '0' and C = '0' then
F <= '0';
elsif...
....
end if;
end process;
method2:
process(A,B,C)
begin
F <= A or B or C;
if (A = '1' and B = '0' and C = '1') or (A = '1' and B = '1' and C = '0') then
F <= '0';
end if;
end process;
and so on...
end process;
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