BatchMarker
A named undo batch.
In the namespace construct::ops. Declared in src/libs/libconstruct/construct/ops/BatchMarker.hpp.
Detailed description
The marker names the batch and describes it. It does not say which commands belong to the batch: each ConstructUndoCommand carries its batch id (opal-plan-edit-sessions §PES-5.1). The old start and end stack indexes went stale when a macro was open, when later commands were pushed, and when the stack was cleared.