Develop and Register Custom Functions

[mathlang]

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Version of ClosedXML

v0.94.2

What is the current behavior?

If an Excel workbook uses custom VBA functions, ClosedXML will fail to parse the formulas because it cannot interpret the custom function

What is the expected behavior or new feature?

I was wondering if you guys ever considered supporting custom functions. At very high level, it could be achieved by making certain classes public or creating new interfaces (CalcEngine, CalcEngineFunction, Expression, etc), with added validations and logic.

I want to discuss this before spending time developing it.

[peetn]

Hello,
I found this topic and I'm also interested.
I have a worksheet with a custom VBA function. Cells that use that custom function anywhere in their formula tree (this cell or a referenced cell or one of their references...) indeed cannot be calculated.
What is the suggested approach here.
Since I see that sometimes the CachedValue (or ValueCached) is not the same as if you would open the file in Excel.
Saving the file in Excel seems to update the CachedValue in a good way. But I don't know why it is not always guaranteed to be correct.
So currently I can't rely on the CachedValue in those cases.
Also there is no way to know if the CachedValue might be incorrect...
Any suggestion is welcome.
Thanks