class Jekyll::Drops::SiteDrop

def documents

additional computation of `Site#documents`.
array shouldn't thereafter change and can therefore be safely memoized to prevent
Since this method will be called after `Site#pre_render` hook, the `Site#documents`

latest state of the attribute.
`Site#documents` cannot be memoized so that `Site#docs_to_write` can access the
def documents
  @documents ||= @obj.documents
end