doc: Remove reference to old hook system.

* doc/api.texi (Agendas): Rewrite example code that used obsolete hook
  API.

1 files changed, 3 insertions, 2 deletions

diff --git a/doc/api.texi b/doc/api.texi
index 8e3ba98..33c9759 100644
--- a/doc/api.texi
+++ b/doc/api.texi
@@ -2604,11 +2604,12 @@ the current time.  This is where @code{after} comes in handy:
 
 Time units in the agenda are in no way connected to real time.  It's
 up to the programmer to decide what agenda time means.  A simple and
-effective approach is to map each call of the update hook
+effective approach is to map each call of the update procedure
 (@pxref{Kernel}) to 1 unit of agenda time, like so:
 
 @example
-(add-hook! update-hook (lambda (dt) (update-agenda 1)))
+(define (update dt)
+  (update-agenda 1))
 @end example
 
 It is important to call @code{update-agenda} periodically, otherwise