+;; This procedure is used by Emacs-Guix up to 0.5.1.1, so keep it for now.
+;; See <https://github.com/alezost/guix.el/issues/30>.
+(define-deprecated find-newest-available-packages
+ find-packages-by-name
+ (mlambda ()
+ "Return a vhash keyed by package names, and with
+associated values of the form
+
+ (newest-version newest-package ...)
+
+where the preferred package is listed first."
+ (fold-packages (lambda (p r)
+ (let ((name (package-name p))
+ (version (package-version p)))
+ (match (vhash-assoc name r)
+ ((_ newest-so-far . pkgs)
+ (case (version-compare version newest-so-far)
+ ((>) (vhash-cons name `(,version ,p) r))
+ ((=) (vhash-cons name `(,version ,p ,@pkgs) r))
+ ((<) r)))
+ (#f (vhash-cons name `(,version ,p) r)))))
+ vlist-null)))
+
+(define (fold-available-packages proc init)
+ "Fold PROC over the list of available packages. For each available package,
+PROC is called along these lines:
+
+ (PROC NAME VERSION RESULT
+ #:outputs OUTPUTS
+ #:location LOCATION
+ …)
+
+PROC can use #:allow-other-keys to ignore the bits it's not interested in.
+When a package cache is available, this procedure does not actually load any
+package module."
+ (define cache
+ (load-package-cache (current-profile)))
+
+ (if (and cache (cache-is-authoritative?))
+ (vhash-fold (lambda (name vector result)
+ (match vector
+ (#(name version module symbol outputs
+ supported? deprecated?
+ file line column)
+ (proc name version result
+ #:outputs outputs
+ #:location (and file
+ (location file line column))
+ #:supported? supported?
+ #:deprecated? deprecated?))))
+ init
+ cache)
+ (fold-packages (lambda (package result)
+ (proc (package-name package)
+ (package-version package)
+ result
+ #:outputs (package-outputs package)
+ #:location (package-location package)
+ #:supported?
+ (->bool (supported-package? package))
+ #:deprecated?
+ (->bool
+ (package-superseded package))))
+ init)))
+
+(define* (fold-packages proc init
+ #:optional
+ (modules (all-modules (%package-module-path)
+ #:warn
+ warn-about-load-error))
+ #:key (select? (negate hidden-package?)))
+ "Call (PROC PACKAGE RESULT) for each available package defined in one of
+MODULES that matches SELECT?, using INIT as the initial value of RESULT. It
+is guaranteed to never traverse the same package twice."