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-rw-r--r-- | doc/guix.texi | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/doc/guix.texi b/doc/guix.texi index b6d041d73e..25c08b9f06 100644 --- a/doc/guix.texi +++ b/doc/guix.texi @@ -21090,16 +21090,16 @@ services. Otherwise, it must be a one-argument procedure. The procedure is called by @code{fold-services} and is passed a list of values collected from -extensions. It must return a value that is a valid parameter value for -the service instance. +extensions. It may return any single value. @item @code{extend} (default: @code{#f}) If this is @code{#f}, services of this type cannot be extended. Otherwise, it must be a two-argument procedure: @code{fold-services} -calls it, passing it the initial value of the service as the first argument -and the result of applying @code{compose} to the extension values as the -second argument. +calls it, passing it the initial value of the service as the first +argument and the result of applying @code{compose} to the extension +values as the second argument. It must return a value that is a valid +parameter value for the service instance. @end table @xref{Service Types and Services}, for examples. |