in src/asl-utils/asl/definitions.ts [618:626]
export function isMapWithIterator(state: StateDefinition | undefined | null): state is DeprecatedMapWithIterator {
return (
!!state &&
state.Type === 'Map' &&
!!(state as DeprecatedMapState).Iterator &&
typeof (state as DeprecatedMapState).Iterator === 'object' &&
!Array.isArray((state as DeprecatedMapState).Iterator)
)
}