For in VHDL

-- VHDL doesn't have a direct equivalent to Go's 'for' loops.
-- We'll use processes and while loops to demonstrate similar concepts.

library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
use IEEE.NUMERIC_STD.ALL;

entity ForLoopExample is
end ForLoopExample;

architecture Behavioral of ForLoopExample is
    -- Declare a procedure for printing (simulating fmt.Println)
    procedure print(constant str : in string) is
    begin
        report str severity note;
    end procedure;

begin
    -- The most basic type, with a single condition.
    process
        variable i : integer := 1;
    begin
        while i <= 3 loop
            print("i = " & integer'image(i));
            i := i + 1;
        end loop;
        wait;
    end process;

    -- A classic initial/condition/after loop.
    process
        variable j : integer := 0;
    begin
        while j < 3 loop
            print("j = " & integer'image(j));
            j := j + 1;
        end loop;
        wait;
    end process;

    -- Simulating 'range' iteration
    process
    begin
        for i in 0 to 2 loop
            print("range " & integer'image(i));
        end loop;
        wait;
    end process;

    -- Simulating an infinite loop with break
    process
    begin
        loop
            print("loop");
            exit;  -- This is equivalent to 'break' in Go
        end loop;
        wait;
    end process;

    -- Simulating continue with next
    process
    begin
        for n in 0 to 5 loop
            if n mod 2 = 0 then
                next;  -- This is equivalent to 'continue' in Go
            end if;
            print(integer'image(n));
        end loop;
        wait;
    end process;

end Behavioral;

In VHDL, we don’t have direct equivalents to Go’s for loops, but we can achieve similar functionality using processes and while loops. Here’s an explanation of the VHDL code:

We define a print procedure to simulate Go’s fmt.Println function.
Each loop type is implemented in a separate process:
- The basic condition loop is implemented using a while loop.
- The classic for loop is also implemented using a while loop.
- The range-based loop is implemented using VHDL’s for loop.
- The infinite loop with break is implemented using an infinite loop with an exit statement.
- The loop with continue is implemented using VHDL’s for loop with the next statement.
VHDL doesn’t have a built-in range function like Go, so we use a for loop with explicit bounds.
The break statement in Go is equivalent to exit in VHDL.
The continue statement in Go is equivalent to next in VHDL.
Each process ends with a wait statement to prevent it from restarting indefinitely.

Note that this VHDL code is not synthesizable and is meant for simulation purposes only. In real VHDL designs, you would typically use these constructs within clocked processes or combinatorial logic blocks.

To run this VHDL code, you would need to use a VHDL simulator such as ModelSim or GHDL. The output would be similar to the Go example, showing the results of each loop type.

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For in VHDL