A domain specification is written as a flat YAML list, where each signal and branch is a self-contained YAML list element.
The YAML list is a single file, called a vspec file.
A vspec can, in addition to a YAML list, also contain include directives.
An include directive refers to another vspec file that is to replace the
directive, much like #include in C/C++. Please note that, from a YAML
perspective, the include directive is just another comment.
Tree nodes are addressed, left-to-right, from the root of the tree
toward the node itself. Each element in the name is delimited with
a period ("."). The element hops from the root to the leaf is called path.
For example, the dimming status of the rearview mirror in the cabin is addressed:
Cabin.RearviewMirror.Dimmed
If there are an array of elements, such as door rows 1-3, they will be addressed with an index branch:
Cabin.Door.Row1.Left.IsLocked
Cabin.Door.Row1.Left.Window.Position
Cabin.Door.Row2.Left.IsLocked
Cabin.Door.Row2.Left.Window.Position
Cabin.Door.Row3.Left.IsLocked
Cabin.Door.Row3.Left.Window.Position
In a similar fashion, seats are located by row and their left-to-right position.
Cabin.Seat.Row1.Pos1.IsBelted # Left front seat
Cabin.Seat.Row1.Pos2.IsBelted # Right front seat
Cabin.Seat.Row2.Pos1.IsBelted # Left rear seat
Cabin.Seat.Row2.Pos2.IsBelted # Middle rear seat
Cabin.Seat.Row2.Pos3.IsBelted # Right rear seat
The exact use of PosX elements and how they correlate to actual
positions in the car, is dependent on the actual vehicle using the
spec.
If a new leaf node is defined, all parent branches included in its name must be included as well, as shown below:
[Signal] Cabin.Door.Row1.Left.IsLocked
[Branch] Cabin.Door.Row1.Left
[Branch] Cabin.Door.Row1
[Branch] Cabin.Door
[Branch] Cabin
The branches do not have to be defined in any specific order as long as each branch component is defined somewhere in the vspec file (or an included vspec file).