diff options
| -rw-r--r-- | doc/guix.texi | 13 | ||||
| -rw-r--r-- | gnu/services.scm | 27 |
2 files changed, 29 insertions, 11 deletions
diff --git a/doc/guix.texi b/doc/guix.texi index bb86195a25..22b4c6a6b7 100644 --- a/doc/guix.texi +++ b/doc/guix.texi @@ -13518,6 +13518,14 @@ following expression returns a list that contains all the services in %desktop-services) @end lisp +Alternatively, the @code{modify-services} macro can be used: + +@lisp +(modify-services %desktop-services + (delete avahi-service-type)) +@end lisp + + @unnumberedsubsec Instantiating the System Assuming the @code{operating-system} declaration @@ -17787,9 +17795,8 @@ and tty8. (service slim-service-type (slim-configuration (display ":1") (vt "vt8"))) - (remove (lambda (service) - (eq? (service-kind service) gdm-service-type)) - %desktop-services)))) + (modify-services %desktop-services + (delete gdm-service-type))))) @end lisp @end defvr diff --git a/gnu/services.scm b/gnu/services.scm index ddd1bac30c..e7da0a026d 100644 --- a/gnu/services.scm +++ b/gnu/services.scm @@ -2,6 +2,7 @@ ;;; Copyright © 2015, 2016, 2017, 2018, 2019, 2020 Ludovic Courtès <ludo@gnu.org> ;;; Copyright © 2016 Chris Marusich <cmmarusich@gmail.com> ;;; Copyright © 2020 Jan (janneke) Nieuwenhuizen <janneke@gnu.org> +;;; Copyright © 2020, 2021 Ricardo Wurmus <rekado@elephly.net> ;;; ;;; This file is part of GNU Guix. ;;; @@ -109,7 +110,11 @@ %boot-service %activation-service - etc-service)) + etc-service) + #:re-export (;; Note: Re-export 'delete' to allow for proper syntax matching + ;; in 'modify-services' forms. See + ;; <https://debbugs.gnu.org/cgi/bugreport.cgi?bug=26805#16>. + delete)) ;;; Comment: ;;; @@ -279,7 +284,11 @@ singleton service type NAME, of which the returned service is an instance." (service type value))) (define-syntax %modify-service - (syntax-rules (=>) + (syntax-rules (=> delete) + ((_ svc (delete kind) clauses ...) + (if (eq? (service-kind svc) kind) + #f + (%modify-service svc clauses ...))) ((_ service) service) ((_ svc (kind param => exp ...) clauses ...) @@ -309,16 +318,18 @@ TYPE. Consider this example: (mingetty-service-type config => (mingetty-configuration (inherit config) - (motd (plain-file \"motd\" \"Hi there!\"))))) + (motd (plain-file \"motd\" \"Hi there!\")))) + (delete udev-service-type)) It changes the configuration of the GUIX-SERVICE-TYPE instance, and that of -all the MINGETTY-SERVICE-TYPE instances. +all the MINGETTY-SERVICE-TYPE instances, and it deletes instances of the +UDEV-SERVICE-TYPE. -This is a shorthand for (map (lambda (svc) ...) %base-services)." +This is a shorthand for (filter-map (lambda (svc) ...) %base-services)." ((_ services clauses ...) - (map (lambda (service) - (%modify-service service clauses ...)) - services)))) + (filter-map (lambda (service) + (%modify-service service clauses ...)) + services)))) ;;; |