typen | Strong Type Hints with Traits | Validation library

I think your solution seems fine to me. Another option would be to join both data frame parts by date, and then pivot longer.

For more than one pair, I'd split the data frame into n chunks of 2 columns, and then rename all date columns, and then use purrr::reduce

From How to select namespace value via XPath:

In the following way, you can get a single value per line without any other characters

Which of the two approaches is better?

Neither, see option 3 below.

How can I prevent the program from creating a container that holds anything other than std::variant<>?

Without seeing your CSS for the carousel and carousel items, have you tried using the bootstrap class mx-auto to set the left and right margin values to auto, this will center an element that has a width defined.

time requests the current time in seconds as an integer. if your program takes less than a second to execute, then you will "seed" the random number generator with the same value every time. pseudo random number generators (i.e. your rand() call) return a deterministic series of values based on this state you seeded.

as @Scheff said, you're much better off just seeding once (probably at the beginning of the program) and then just calling rand() when you need it. note that srand and rand are old historical artifacts from C, and you're much better off using more modern generators that come with recent C++ compilers

see the docs on c++ random number generators for more information

Normally, you'd have people asking for what you've tried so far and your code, but I understand you're really in the dark on how to even get started with this problem.

If you need the Python script to be able to step in after the user has interacted with the site, you're in for a massive challenge. There are many variables, like what browser is being used, on what operating system, at what resolution, with what settings, etc.

Interacting with a live application will be fairly hard, although not impossible. If the site can be operated entirely using the keyboard and you can find some reliable sequence of keyboard inputs that find the right controls to send input to, that could be an approach and libraries like pywin32 could provide access to the API call you'd need to send input to the screen.

However, a better approach may be to just cut out the user altogether and have the script perform all the interaction. You can do that through something like selenium and a driver like ChromeDriver that basically allows you to operate a website, with all its scripting, like a user would.

You should probably look into either of these approaches and come up with a basic attempt to ask more specific questions if you run into problems.

Phase seems to be wrong. If I change refchecks to parser then the plugin with the following component

You're nearly there. This is only a syntactic confusion. You cannot create a trigger that fires BEFORE or AFTER an insert or update or delete of a view, but you can create a trigger that fires INSTEAD OF an insert or update or delete:

TABLE BEFORE / AFTER insert or update or delete VIEW INSTEAD OF insert or update or delete

And, as @Belayer writes, you don't (and shouldn't) use SELECT, use the automatically prepared record called :new for the new values during insert or update, or the record ':old' for the old values during update or delete.

Your trigger would look something like: