Hi,

Could anyone please explain to me how can this be used? I am a programmer myself (not in python, but I do know a few things), but it's very hard to get started with something with no base.

Official documentation only mentions the function exists, there are no examples how to use it.

When contacting support, they insisted this is not in their domain, and that I have to pay someone to develop it for me, even thought I don't need anything developed, I only want to know how to use a feature that is already there.

I have created a custom module with "odoo-bin scaffold module_name module_path" command, and added some logic under models, installed it, but with no success.
The error is always either "Method 'f' must start with the '_report_custom_engine_' prefix." or "Invalid method “_report_custom_engine_f”".

If someone can give me a working example how to use this, in version 18, I would be very grateful. I just want to know how to define a function that can use a given parameter and then do something with it. So the most simplest example would be, if I put in number 1 in Subformula, that a number 1 is shown on the report as a result, as I can handle the logic myself afterwards.

Thank you in advance