package-used-by-list

package-used-by-list package → used-by-list

package — a package designator.

used-by-list — a list of package objects.

package-used-by-list returns a list of other packages that use package.

(package-used-by-list (make-package 'temp)) → () 
(make-package 'trash :use '(temp)) → #<PACKAGE "TRASH"> 
(package-used-by-list 'temp) → (#<PACKAGE "TRASH">)

Should signal an error of type type-error if package is not a package.

use-package, unuse-package