empty array litteral

[JR]

Hi all!

According to std.standard:

TYPE string IS ARRAY ( positive RANGE <> OF character);

"hello" is a valid string litteral
"" is a valid string litteral too, it is the empty string.


Let

TYPE foo IS ARRAY ( positive RANGE <> OF integer);

(0, 1, 1, 2, 3, 5) is a valid foo litteral

What is the litteral for an empty foo?

Thx

Julien

 

[Tricky]

> Hi all!
> TYPE string IS ARRAY ( positive RANGE <> OF character);
> "hello" is a valid string litteral

> "" is a valid string litteral too, it is the empty string.
> TYPE foo IS ARRAY ( positive RANGE <> OF integer);
> (0, 1, 1, 2, 3, 5) is a valid foo litteral
> What is the litteral for an empty foo?
> Julien

That is an interesting question.

You can make a null constant like this:

constant NULL_FOO : foo(1 downto 2) := (others => 0);

then use the constant in place of a literal.