Access vba or caller in converter for UDFs

[audetto]

I would like to know if it is possible to access vba or caller inside a converter.

The use case is a function returning an object which is saved into a python dictionary and the key returned to Excel.
I would like to use the cell name to avoid constantly creating new objects.

I could do this inside the function, but I like the idea of the converter so that I keep this Excel logic separated. And when calling it from python, it does not alter the behaviour.

Moreover I could use a decorator around the function, but that would alter the normal python behaviour.

I really like the idea of the converters.

Any suggestion?

[fzumstein]

If you could add an example, that would certainly help. Converters are only good for manipulating the values, but you might be able to pull something off by writing an Accessor. Since they are currently not documented, you could take a look at one here:
https://github.com/xlwings/xlwings/blob/master/xlwings/conversion/standard.py#L168-L182

[audetto]

I will provide an example, but meanwhile I found a way to achieve it

excel = xw.apps.active
application = excel.api.Application
caller = excel.Caller

address = caller.Address

This works in converters, even if they don't have access to the caller provided by xw.

[fzumstein]

I'd rather use xw.Book.caller().app instead of xw.app.active

[audetto]

here is an example

https://github.com/audetto/xlwings-demo/blob/master/main.py

in particular, https://github.com/audetto/xlwings-demo/blob/master/main.py#L16

With this technique, objects are never deleted.

The idea is almost the same as get_cache_key in

xlwings/xlwings/udfs.py

Line 411 in f72bc83

def get_cache_key(func, args, caller):

But with the suggestion above, once can bypass the whole caller thing. Are there any drawbacks?

[fzumstein]

I am closing this as I think it's a dupe of #555.