<div dir="ltr">I wonder what would break if we got rid of this error:<br><br>In [5]: dobj = ds.all_data() + ds2.all_data()<br>------------------------------<wbr>------------------------------<wbr>---------------<br>YTBooleanObjectsWrongDataset  <wbr>            Traceback (most recent call last)<br>~/Documents/yt-git-fixes/yt/mo<wbr>ds.py in <module>()<br>----> 1 dobj = ds.all_data() + ds2.all_data()<br><br>~/Documents/yt-git-fixes/yt/da<wbr>ta_objects/data_containers.py in __add__(self, other)<br>   1423<br>   1424     def __add__(self, other):<br>-> 1425         return self.__or__(other)<br>   1426<br>   1427     def __sub__(self, other):<br><br>~/Documents/yt-git-fixes/yt/da<wbr>ta_objects/data_containers.py in __or__(self, other)<br>   1399             raise YTBooleanObjectError(other)<br>   1400         if self.ds is not other.ds:<br>-> 1401             raise YTBooleanObjectsWrongDataset()<br>   1402         # Should maybe do something with field parameters here<br>   1403         return YTBooleanContainer("OR", self, other, ds = self.ds)<br><br>YTBooleanObjectsWrongDataset: Boolean data objects must share a common dataset object.<div class="gmail_extra"><br></div></div>