asdf:component-sideway-dependencies
(asdf:component-sideway-dependencies system)
Reader: the system's :depends-on names, in order. For a package-inferred
system these are the names derived from the component file's own defpackage,
sub-system names included — which is what rove's
package-inferred-system-component-names filters by the primary's prefix.
Backend support
Works on all four backends.