html_url,issue_url,id,node_id,user,created_at,updated_at,author_association,body,reactions,performed_via_github_app,issue
https://github.com/pydata/xarray/issues/6827#issuecomment-1382154696,https://api.github.com/repos/pydata/xarray/issues/6827,1382154696,IC_kwDOAMm_X85SYgHI,35968931,2023-01-13T17:14:33Z,2023-01-13T17:14:33Z,MEMBER,"@gabicca given that we do say in our docs that [we don't recommend subclassing xarray objects](https://docs.xarray.dev/en/stable/internals/extending-xarray.html), I'm going to close this issue as a downstream ""subclass at your own risk"" problem. If you would like it to be easier to subclass, [we would welcome your input here](https://github.com/pydata/xarray/issues/3980).","{""total_count"": 1, ""+1"": 1, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,1318173644
https://github.com/pydata/xarray/issues/6827#issuecomment-1220524864,https://api.github.com/repos/pydata/xarray/issues/6827,1220524864,IC_kwDOAMm_X85Iv7tA,33315687,2022-08-19T10:39:58Z,2022-08-19T10:39:58Z,NONE,"I'll leave that with you guys to decide. I've reported it, it's been looked at, and it has a record of it. So if the code is as you intended, I don't mind if the issue is closed.","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,1318173644
https://github.com/pydata/xarray/issues/6827#issuecomment-1215314423,https://api.github.com/repos/pydata/xarray/issues/6827,1215314423,IC_kwDOAMm_X85IcDn3,2448579,2022-08-15T16:32:43Z,2022-08-15T16:32:43Z,MEMBER,Shall we close? It seems like the current code is what we want.,"{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,1318173644
https://github.com/pydata/xarray/issues/6827#issuecomment-1198556515,https://api.github.com/repos/pydata/xarray/issues/6827,1198556515,IC_kwDOAMm_X85HcIVj,14371165,2022-07-28T19:39:41Z,2022-07-28T19:40:08Z,MEMBER,Because we want to get out the same type of Dataset (subclassed or not) as we input. That's what the T_Dataset type implies. And since we forced a Dataset at the end that wasn't the case. ,"{""total_count"": 3, ""+1"": 3, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,1318173644
https://github.com/pydata/xarray/issues/6827#issuecomment-1196538785,https://api.github.com/repos/pydata/xarray/issues/6827,1196538785,IC_kwDOAMm_X85HUbuh,33315687,2022-07-27T10:15:16Z,2022-07-27T10:15:16Z,NONE,"> In the example the naming and meaning of the arguments of the `__init__` method are different from the `Dataset` base class.
>
> Subclassing is often more reliable when it adheres to the Liskov Substitution Principle which states that objects of a superclass should be replaceable with objects of its subclasses and in other words: a subclass should only add functionality and not reduce it.
>
> There are some other workarounds though:
>
> If all you need is a convenient custom constructor then you could add a `classmethod` factory method to your subclass or even just use a plain function which returns a `Dataset`.
>
> Another option is to convert your `MyDataset` instances to plain `Dataset` instances before passing them into `xarray.concat`, e.g. `xarray.concat([ds.to_dataset() for ds in [ds1, ds2, ds3]], dim=""coord1"")`
>
> where your subclass may define as a convenience method:
>
> ```
> def to_dataset(self):
> """"""Convert to plain Dataset.""""""
> return xarray.Dataset(self, attrs=self.attrs)
> ```
Thank you for the answer. I'll look into implementing one of your suggestions (they're much better than what I had in mind).
I still don't understand the change that causes the error, though. If you want to instantiate a Dataset object, which you clearly do according to the args you pass in, why did that line have to be changed from explicitly calling Dataset? (By ""you"" I don't mean you personally, unless you actually made the change :) )","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,1318173644
https://github.com/pydata/xarray/issues/6827#issuecomment-1195752253,https://api.github.com/repos/pydata/xarray/issues/6827,1195752253,IC_kwDOAMm_X85HRbs9,32801740,2022-07-26T17:10:02Z,2022-07-26T18:15:38Z,CONTRIBUTOR,"In the example the naming and meaning of the arguments of the `__init__` method are different from the `Dataset` base class.
Subclassing is often more reliable when it adheres to the Liskov Substitution Principle which states that objects of a superclass should be replaceable with objects of its subclasses and in other words: a subclass should only add functionality and not reduce it.
There are some other workarounds though:
If all you need is a convenient custom constructor then you could add a `classmethod` factory method to your subclass or even just use a plain function which returns a `Dataset`.
Another option is to convert your `MyDataset` instances to plain `Dataset` instances before passing them into `xarray.concat`, e.g.
```xarray.concat([ds.to_dataset() for ds in [ds1, ds2, ds3]], dim=""coord1"")```
where your subclass may define as a convenience method:
```
def to_dataset(self):
""""""Convert to plain Dataset.""""""
return xarray.Dataset(self, attrs=self.attrs)
````","{""total_count"": 2, ""+1"": 2, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,1318173644