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hi. I came across the dot "." in a testbench. i have no idea what is the function. Normally we will on only see it in the library declaration. However it is used in the process.

Is there anyone know abt it?

Thanks

it is used to select an element in a record like this:

Code: Select all

type my_record_t is record
  a : integer;
  b : std_logic;
end record my_record_t;

signal r : my_record_t;


...

r.a <= 10;
r.b <= '1';

input <= r.a;
valid <= r.b;

...etc.


Or to dereference a pointer with the .all field (like the * operator in C/C++)

Code: Select all

type my_record_ptr_t is access my_record_t;

variable ptr : my_record_ptr_t;

....
ptr := new my_record_t;

ptr.all := (10, '0');
--or
ptr.all.a := 10;
ptr.all.b := '0';


It helps. thanks