onents.  To this aim, every component manager maintains its
    <EM>component table</EM>, which is a mapping from URLs to components.
    All loading, linking, evaluating, and signature matching is performed
    lazily.  For this reason components are initially returned as lazy
    futures, which either get replaced by the component export (on success)
    or failed.  See the
    description of exception <TT><A href="component.html#Failure"
    >Component.Failure</A></TT> to see how these "asynchronous"
   