Issue a warning when overwriting attributes with accessors instead of erroring

[shoyer]

On the mailing list, @rabernat wrote:

Also, how can I interactively develop an accessor? If I try to
re-register under the same name, I get the error
AccessorRegistrationError: cannot register accessor <class
'main.ExchAccessor'> under name 'exch' for type <class
'xarray.core.dataset.Dataset'> because an attribute with that name
already exists.

In #1080, @smartass101 suggests:

Btw, perhaps it might be better to (perhaps optionally) issue a warning when overriding an existing class attribute during registering instead of completely refusing to do so.

I think this is a good idea, and would nicely solve @rabernat's problem (which might be your problem, too). We could add a new keyword argument (e.g., allow_override=True or warn=True to register_*_accessor) which switches to this new mode.

Should it be the default behavior? It is also possible that warnings instead of errors are enough in general.

[smartass101]

I vote for warning by default. Raising an error brings more inconvenience than it's worth.
Remember to warneach time, not just on first code run.

On November 6, 2016 2:11:54 PM GMT+01:00, Stephan Hoyer notifications@github.com wrote:

On the mailing list, @rabernat wrote:

Also, how can I interactively develop an accessor? If I try to
re-register under the same name, I get the error
AccessorRegistrationError: cannot register accessor <class
'main.ExchAccessor'> under name 'exch' for type <class
'xarray.core.dataset.Dataset'> because an attribute with that name
already exists.

In #1080, @smartass101 suggests:

Btw, perhaps it might be better to (perhaps optionally) issue a
warning when overriding an existing class attribute during registering
instead of completely refusing to do so.

I think this is a good idea, and would nicely solve @rabernat's problem
(which might be your problem, too). We could add a new keyword argument
(e.g., allow_override=True or warn=True to register_*_accessor)
which switches to this new mode.

Should it be the default behavior? It is also possible that warnings
instead of errors are enough in general.

You are receiving this because you were mentioned.
Reply to this email directly or view it on GitHub:
#1082

Sent from my Android device with K-9 Mail. Please excuse my brevity.