Backtrace:
In unknown file:
   ?: 0* [#<procedure #f ()>]
In test.scm:
  41: 1* [load-module "mob_event_test.scm"]
In unknown file:
   ?: 2  [save-module-excursion #<procedure #f ()>]
   ...
   ?: 3  [dynamic-wind #<procedure #f ()> #<procedure #f ()> #<procedure #f ()>]
   ?: 4* [#<procedure #f ()>]
   ?: 5* (let* ((oldname #)) (apply basic-load (if # # filename) reader))
   ?: 6* (and (current-load-port) (port-filename (current-load-port)))
   ?: 7  [port-filename {#<closed: file 0>}]

<unnamed port>: In procedure port-filename in expression (port-filename (current-load-port)):
<unnamed port>: Wrong type argument in position 1: #<closed: file 0>