+(define (%try-use-modules modules location make-hint)
+ "Attempt to load all of MODULES. Report errors as coming from LOCATION, a
+<location> record, and use MAKE-HINT to produce a fix hint."
+ (define (location->string loc)
+ (match loc
+ (#f "")
+ (($ <location> file line column)
+ (format #f "~a:~a:~a: " file line column))))
+
+ (for-each (lambda (module)
+ (catch 'misc-error
+ (lambda ()
+ (process-use-modules `((,module))))
+ (lambda _
+ (raise
+ (apply
+ make-compound-condition
+ (condition
+ (&message
+ (message (format #f (G_ "module ~a not found")
+ module))))
+ (condition
+ (&error-location (location location)))
+ (or (and=> (make-hint module) list)
+ '()))))))
+ modules))
+
+(define (package-module-hint module)
+ (define last-name
+ (match module
+ ((_ ... last)
+ (symbol->string last))))
+
+ (match (find-packages-by-name last-name)
+ (()
+ (condition
+ (&fix-hint
+ (hint (G_ "\
+You may use @command{guix package --show=foo | grep location} to search
+for the location of package @code{foo}.
+If you get the line @code{location: gnu/packages/bar.scm:174:2},
+add @code{bar} to the @code{use-package-modules} form.")))))
+ ((package _ ...)
+ (condition
+ (&fix-hint
+ (hint (format #f (G_ "\
+Try adding @code{(use-package-modules ~a)}.")
+ (basename (location-file (package-location package))
+ ".scm"))))))))
+
+(define (service-module-hint module)
+ (define last-name
+ (match module
+ ((_ ... last)
+ last)))
+
+ (match (lookup-service-types last-name)
+ (()
+ (condition
+ (&fix-hint
+ (hint (format #f (G_ "\
+You may use @command{guix system search ~a} to search for a service
+matching @code{~a}.
+If you get the line @code{location: gnu/services/foo.scm:188:2},
+add @code{foo} to the @code{use-service-modules} form.")
+ last-name last-name)))))
+ ((package _ ...)
+ (condition
+ (&fix-hint
+ (hint (format #f (G_ "\
+Try adding @code{(use-service-modules ~a)}.")
+ (basename (location-file (service-type-location package))
+ ".scm"))))))))
+
+(define-syntax-rule (try-use-modules hint modules ...)
+ (eval-when (expand load eval)
+ (%try-use-modules '(modules ...)
+ (source-properties->location
+ (current-source-location))
+ hint)))
+