Stefan,

Stefan Huchler 写道：
> A the double @ was a typo?

No, it's a documented feature in the Guile manual:

   “You can also directly refer to bindings in a module by using 
   the ‘@’
   syntax.  For example, instead of using the ‘use-modules’ 
   statement from
   above and writing ‘unixy:pipe-open’ to refer to the ‘pipe-open’ 
   from the
   ‘(ice-9 popen)’, you could also write ‘(@ (ice-9 popen) 
   open-pipe)’.
   Thus an alternative to the complete ‘use-modules’ statement 
   would be

     (define unixy:pipe-open (@ (ice-9 popen) open-pipe))
     (define unixy:close-pipe (@ (ice-9 popen) close-pipe))

   There is also ‘@@’, which can be used like ‘@’, but does not 
   check
   whether the variable that is being accessed is actually 
   exported.  Thus,
   ‘@@’ can be thought of as the impolite version of ‘@’ and 
   should only be
   used as a last resort or for debugging, for example.

   Note that just as with a ‘use-modules’ statement, any module 
   that has
   not yet been loaded will be loaded when referenced by a ‘@’ or 
   ‘@@’
   form.” -- (guile)Using Guile Modules

I think I'm done here though.

Good luck,

T G-R