extern fopen(path:String, mode:String):Pointer?
extern fclose(fp:Pointer):Int32

def try_file(path:String):Bool
    f := fopen(path, "r") or return no
    return no unless fclose(f) == 0:Int32
    return yes

try_file("test/pointer.bl") or fail
try_file("asdfasdfasdf") and fail

say "Pointers work!"