FallbackReason

public enum FallbackReason : Equatable, Hashable, Sendable

Why the SDK returned the developer fallback.

Network/cache SDKs (like the iOS/macOS Mixpanel SDK) cannot distinguish “flag does not exist” from “user is not in any rollout” without server-side cooperation — both surface as .flagNotFound for now. Future server changes can add a more specific reason without breaking callers that already switch on this enum.

  • Flag key was not present in the cache or network response.

    Declaration

    Swift

    case flagNotFound

  • Flags were not ready when the sync lookup happened.

    Declaration

    Swift

    case notReady

  • Network fetch failed and no cached/persisted variant was available. Only surfaced on the async getVariant path — getVariantSync cannot distinguish “network error” from “flags never loaded.”

    Declaration

    Swift

    case backendError