Type Definition rustc_middle::ty::RootVariableMinCaptureList

type RootVariableMinCaptureList<'tcx> = FxIndexMap<HirId, MinCaptureList<'tcx>>;

Part of MinCaptureInformationMap; Maps a root variable to the list of CapturedPlace. Used to track the minimum set of Places that need to be captured to support all Places captured by the closure starting at a given root variable.

This provides a convenient and quick way of checking if a variable being used within a closure is a capture of a local variable.