methods to use to try and find a given
module. The entries in <code class="mendoza-code">module/paths</code> will be checked in order,
as it is possible that multiple entries could match.  If a module name
matches a pattern (which usually means that some file exists), then we
use the corresponding loader in <code class="mendoza-code">module/loaders</code> to evaluate that
file, source code, URL, or whatever else we want to derive from the
module name. The resulting value, usually an environment table, is
th