diff options
Diffstat (limited to 'gnu/services/configuration.scm')
-rw-r--r-- | gnu/services/configuration.scm | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/gnu/services/configuration.scm b/gnu/services/configuration.scm index 60965486a7..83da63c1b3 100644 --- a/gnu/services/configuration.scm +++ b/gnu/services/configuration.scm @@ -305,12 +305,13 @@ does not have a default value" field kind))) ;; Ideally this should be an implementation detail, but we export it ;; to provide a simpler API that enables unsetting a configuration -;; field that has a maybe type, but also a default value. +;; field that has a maybe type, but also a default value. We give it +;; a value that sticks out to the reader when something goes wrong. ;; ;; An example use-case would be something like a network application ;; that uses a default port, but the field can explicitly be unset to ;; request a random port at startup. -(define %unset-value 'unset) +(define %unset-value '%unset-marker%) (define (maybe-value-set? value) "Predicate to check whether a 'maybe' value was explicitly provided." |