ProjectedWrite

Where an input stands when its call returns. Both are durable; they differ in whether the view is known to have it.

What a projection attempt left pending: for each entry whose row is not known to be in the view, why. Empty when the view includes the whole record; the marker is then cleared.

The names of the product elements

The name of the type

A ProjectedWrite for a store whose view is one object per record: project writes it and clears the marker, only if the store still holds state, fence and marker alike, and fails otherwise. Nothing is ever left pending.