issue_comments: 535061773

Really? Okay, so that means that currently we don't treat a named DataArray and a single-variable Dataset as if they are the same. For example I would have expected these two operations to give the same result: python objs = [DataArray([0], dims='x', name='a'), DataArray([0], dims='x', name='b')] concat(objs, dim='x') <xarray.DataArray 'a' (x: 2)> array([0, 0]) Dimensions without coordinates: x python objs = [Dataset({'a': ('x', [0])}), Dataset({'b': ('x', [0])})] concat(objs, dim='x') ``` self = Frozen(OrderedDict([('b', <xarray.Variable (x: 1)> array([0]))])), key = 'a'

def __getitem__(self, key: K) -> V:

  return self.mapping[key]

E KeyError: 'a'

xarray/core/utils.py:385: KeyError ```

Is this what we want to do? Surely the first one should also fail, else this is counter-intuitive. I think of a named DataArray and a single-variable Dataset as being the same thing, just a single physical variable? @shoyer am I misunderstanding xarray's data model here?