@create $thing named Generic Sittable Object:Generic Sittable Object
@prop "Generic Sittable"."copyright" "Generic Sittable written by Gary_Severn@LambdaMOO Spring 91, hacked by yduJ@LambdaMOO various later times"
@prop "Generic Sittable Object"."sitting" {} r

@verb "Generic Sittable Object":"sweep" this none this
@program "Generic Sittable Object":sweep
for foo in (this.sitting)
  if ((!valid(foo)) || (foo.location != this.location))
    this.sitting = setremove(this.sitting, foo);
  endif
endfor
.

@verb "Generic Sittable Object":"tell" this none this
@program "Generic Sittable Object":tell
this:sweep();
.

@verb "Generic Sittable Object":"set_sitting" this none this
@program "Generic Sittable Object":set_sitting
this.sitting = args[1];
.

@verb "Generic Sittable Object":"sitting_string" this none this
@program "Generic Sittable Object":sitting_string
verbing = (args ? args[1] | "sitting");
if (player in this.sitting)
  others = listdelete(this.sitting, player in this.sitting);
  you = 1;
else
  others = this.sitting;
  you = 0;
endif
themstr = $string_utils:english_list($list_utils:map_prop(others, "name"));
return this.sitting ? (you ? ((("  You are " + verbing) + " on the ") + this.name) + (others ? " along with " + themstr | "") | ((((("  You see " + themstr) + " ") + verbing) + " on the ") + this.name)) + "." | (("  The " + this.name) + " is invitingly empty.");
.