On Wed, 2018-01-03 at 11:53 +0000, Neil Jerram wrote:
> 
> Well, one Lispy mechanism in that area is hooks.  For example, from
> some 
> of my old code:
> 
> ;; Changes to modem registration state are indicated by calling this
> ;; hook with args STATE and PROPERTIES.  STATE can be 'none, meaning
> ;; that there is currently no modem; 'unregistered, meaning that
> there
> ;; is a modem but it isn't registered with the network; or
> ;; 'registered, meaning that the modem is registered with the
> network.
> ;; If STATE is 'registered, PROPERTIES is an alist of registration
> ;; properties; otherwise PROPERTIES is #f.
> (define registration-hook (make-hook 2))
> 
> (define (add-registration-hook proc)
>    (add-hook! registration-hook proc))
> 
> (define (notify-registration state properties)
>    (run-hook registration-hook state properties))
> 
> Does that serve your purpose at all?
> 
> Best wishes - Neil
> 
> 

I think that should work. Only part I'm not sure about is if you can
have a "one-off" procedure added to a hook... but you could just have
the procedure call remove-hook! to remove itself...?

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