Is there a way to bold part of a character string being passed to add_header_lines() when using the flextable package for R

Question

I'm creating a couple of tables for a Word document using the flextable package, which I'm loving. However, I'm having a little trouble bolding part of the text in my table title. For example, I want the title to read, "Table 1. The rest of my table title." instead of "Table 1. The rest of my table title."

I found this documentation, and after some trial and error I finally got the result I wanted. But it feels like there may be a more straightforward way to get it. Here is my current solution:

library(dplyr)
library(flextable)

mtcars_ft <- flextable(head(mtcars)) %>% 
  # Add a blank title line to top of table
  add_header_lines("") %>% 
  # Use compose to bold "Table #."
  compose(
    i = 1, part = "header",
    value = as_paragraph(
      as_chunk("Table 1. ", props = fp_text(bold = TRUE)),
      "Here is my example mtcars ft."
    ),
  )

Here is a screenshot of my result:

Answer 1

Below a solution that enable to do what you want but also to use auto-numbering in Word so that if updated the numbers and references will be updated.

library(officer)
library(flextable)

mtcars_ft <- flextable(head(mtcars)) %>% set_table_properties(layout = "autofit")

bold_face <- fp_text(bold = TRUE, font.size = 11)

fpar_ <- fpar(
  run_autonum(seq_id = 'tab', 
              bkm = 'a_bkm', pre_label = "Table ", 
              prop = bold_face),
              "Here is my example mtcars ft." )

read_docx() %>% 
  body_add_fpar(fpar_, style = "centered") %>% 
  body_add_flextable(mtcars_ft) %>% 
  print(target = "example.docx")

This is basically what do flextable::set_caption (but with no ability to format the text as you want)