# Structures

The following structures are available globally.

### CastEngine

- `CastEngine`

  Cast engine

  See more

  #### Declaration

  Swift

      public struct CastEngine : RawRepresentable, Hashable

- `MetaData`

  The meta-data object is a dictionary that can contain arbitrary data.

  #### Declaration

  Swift

      public struct MetaData : Codable, Hashable

- `SideloadedTrack`

  This object describes a text or thumbnail track that can be side loaded.

  #### Declaration

  Swift

      public struct SideloadedTrack : Codable, Hashable

### AnalyticsAPI

- `AnalyticsErrorReport`

  A value type describing an error event to be sent to the analytics backend.

  Use this type to encapsulate the error code, human‑readable message, optional contextual metadata, and severity. Instances are typically created in error handling paths and forwarded via `filterOutgoingErrorReport`.

  See more

  #### Declaration

  Swift

      public struct AnalyticsErrorReport

- `AbrConfiguration`

  The ABR Configuration

  Remark

  Usable in the Castlabs Player only. Has no effect on AVPlayer.
  See more

  #### Declaration

  Swift

      public struct AbrConfiguration : Codable, Hashable