::method init
expose readers writers
readers = 0
writers = 0

::method read unguarded
/* Read if no one is writing */
expose writers readers
guard on when writers = 0
readers = readers + 1
guard off

/* Read the data */
say "Reading (writers:" writers", readers:" readers")."
guard on
readers = readers - 1

::method write unguarded
/* Write if no-one is writing or reading */
expose writers readers
guard on when writers + readers = 0
writers = writers + 1

/* Write the data */
say "Writing (writers:" writers", readers:" readers")."
writers = writers - 1