How do you implement this when else statement in VHDL?

Question

I have the following example from an answer on a previous post on Stackexchange Electrical Engineering:

show_out <= show when player = '0' else '0';
set_out <= set when player = '0' else '0';
input_out <= input when player = '0' else "00000000";
-- etc.
show_out2 <= show when player = '1' else '0';
set_out2 <= set when player = '1' else '0';
input_out2 <= input when player = '1' else "00000000";
-- etc.

I want to insert it in a process like the one below:

architecture Behavioral of twoplayermux1 is
begin
 process (show,set,input,try,player)
 begin
-- INSERT THE LINES OF WHEN ELSE ASSIGNMENTS HERE...
 end process twoplayermux1;
end Behavioral;

How does the syntax looks like for that?

• Oldfart: Just replace it with set of if ...else.. endif. (Why do you insists on using a process?)
• user110971: I saw your previous post. I think what you are having a problem with is that you are assigning different outputs in each case. So you need to assign both show_out and show_out2 in all your separate cases. The way you have written it, the synthesizer will set show_out = show and show_out2 = show permanently.
• user164324: @user110971 What about two different if statements in-between "begin" and "end process twoplayermux1"?

Answer 1

The syntax is the same whether inside or outside a process using VHDL-2008. The example slide below shows the syntax. Source for image is: enter link description here. As mentioned in the comment on your question, there's no real need for the process.

enter image description here

• JHBonarius: There's also the case-statement
• Caleb Reister: Note that some synthesis tools (including Vivado) don't support when statements in processes.
• user_007: @CalebReister have you tried specifying VHDL 2008 type in Vivado? I have certainly synthesized this syntax in Vivado. Perhaps it also depends on your Vivado version. It works in Vivado 2018.3.
• Caleb Reister: @user_007 Yes I did, but I would have been using Vivado 2017.4 when I last tried it.