Module selection 

Shared collection selection models: SelectionModel, the compact index-based form for immutable local lists, and KeySelection, which keeps selection attached to stable model keys and represents select-all as a complement, for mutable, virtualized and partially resident collections.

Several toolkit widgets surface a list of homogeneous items to select — DataTable list mode, the file picker, the file explorer’s views — and they all need the same selection semantics, so that logic lives here once instead of being re-derived in each widget.

Structs

KeySelection

Stable-key multi-selection for virtualized and mutable collections.

SelectionModel

Index-based multi-selection state. Indices are opaque usizes the owning widget assigns to its items (typically the row/cell order).