Problem with declarations

[jakacki]

Hello,

I have these two declarations in Verilog-AMS:

nature Base ... endnature;
nature Derived : Base ... endnature;

Neither Base nor Derived define idt_nature.

What is the correct value of Derived.idt_nature ?

There are (at least) two interpretations of LRM, I am not
sure which one is correct:

(1) Base.idt_nature is not defined, so default is used,
thus Base.idt_nature==Base. Derived inherits all attributes
from Base, consequently Derived.idt_nature==Base.

(2) Base.idt_nature is not defined, so Derived does not
inherit any definition of idt_nature. Consequently
Derived.idt_nature is not defined. Thus, by default,
Base.idt_nature==Base and Derived.idt_nature==Derived.

Thanks for any guidance
Grzegorz