Anatomy

Roles and structural relations inside a compound prototype family

anatomy describes stable roles and relations inside a compound prototype family, such as root, trigger, and content.

It answers structural questions like:

• which parts belong to the same family
• which role each part claims
• which roles may contain other roles

It does not, by itself, define business collection semantics.

Some compound interactions need more than role membership. They also need an ordered host view:

• which item comes before or after the current one
• what index the current item occupies among peers
• whether the effective host order has changed

Proto UI handles this as an enhancement under anatomy, not as a new top-level collection runtime concept. anatomy.order is that ordered host view.

It provides:

• ordered queries such as partsOf(), indexOfSelf(), prevOfSelf(), nextOfSelf()
• an internal order-change signal via version()

This keeps the layering explicit:

• anatomy defines family membership and structural relations
• anatomy.order projects those parts into an ordered host view
• higher-level hooks may build collection behavior on top of that view

anatomy.order is still not a full collection model. It does not define:

• selection state
• item business metadata
• roving focus policy
• keyboard paging policy

Those belong to higher-level hooks such as asCollection(), not to anatomy itself.