what is section_div in analyze?

[clarkliming]

there is an argument called "section_div" in analyze function. It says that it will be used in "splits" (how?) but it seems that this is not working

lyt <- basic_table() %>%
    split_rows_by("ARM") %>%
    analyze("AGE", afun = list_wrap_x(summary) , format = "xx.xx", section_div = "")
tbl <- build_table(lyt, DM)
tbl

lyt <- basic_table() %>%
    split_rows_by("ARM", section_div =  "") %>%
    analyze("AGE", afun = list_wrap_x(summary) , format = "xx.xx")
tbl <- build_table(lyt, DM)
tbl

gives

                 all obs
————————————————————————
A: Drug X               
  Min.            20.00 
  1st Qu.         29.00 
  Median          33.00 
  Mean            34.91 
  3rd Qu.         39.00 
  Max.            60.00 
B: Placebo              
  Min.            21.00 
  1st Qu.         29.00 
  Median          32.00 
  Mean            33.02 
  3rd Qu.         37.00 
  Max.            55.00 
C: Combination          
  Min.            22.00 
  1st Qu.         30.00 
  Median          33.00 
  Mean            34.57 
  3rd Qu.         38.00 
  Max.            53.00 


                 all obs
————————————————————————
A: Drug X               
  Min.            20.00 
  1st Qu.         29.00 
  Median          33.00 
  Mean            34.91 
  3rd Qu.         39.00 
  Max.            60.00 

B: Placebo              
  Min.            21.00 
  1st Qu.         29.00 
  Median          32.00 
  Mean            33.02 
  3rd Qu.         37.00 
  Max.            55.00 

C: Combination          
  Min.            22.00 
  1st Qu.         30.00 
  Median          33.00 
  Mean            34.57 
  3rd Qu.         38.00 
  Max.            53.00 

apparently, with section_div in analyze is not doing something