Adding some formatting options

[rix133]

I tried to address simple issues from #4 the first commit is only simple stuff but I forgot to change the parameter count {"C_write_data_frame_list", (DL_FUNC) &C_write_data_frame_list, 5},
I totally understand If this would be rejected as you stated that this might make the code harder to maintain.

[jeroen]

Hey, thanks for your contribution. Are you aware of the new openxlsx2 package by @JanMarvin? It seems to have a lot of formatting functionality built-in: https://janmarvin.r-universe.dev/openxlsx2/doc/manual.html

The vignettes are also very extensive: https://janmarvin.r-universe.dev/openxlsx2

In what way would we benefit from duplicating this functionality in writexl?

[rix133]

It's totally up to you. :) I just prefer to use writexl as it is fast and works well. I just wanted those convenience options to the result. I can't install openxlsx2 from Bioconductor or CRAN so I have not been testing openxlsx2 (not available for 4.3.1 on windows) but I can see that this has a lot of functionality.
I like the simplicity to just write writexl::write_xlsx(df, "./results/output.xlsx") when I have to share something with people not using R and almost always they have to freeze top row, adjust column widths to see the column names and and set autofilter when they explore the result. As I undesrtand from #4 I'm not alone.

[jmcnamara]

In what way would we benefit from duplicating this functionality in writexl?

If we had done it first in writexl we wouldn't be duplicating. A lot of the formatting functionality was already available in libxlsxwriter.

[rix133]

In what way would we benefit from duplicating this functionality in writexl?

If we had done it first in writexl we wouldn't be duplicating. A lot of the formatting functionality was already available in libxlsxwriter.

exactly, I only used the options that the current bundled version of libxlsxwriter provides