Shiny Tags Throwing Errors

shiny
,
#1

I am trying to create an about page for my Shiny App with a basic app description. Part of this involves some bullet points. I ended up using the following code in the tab UI:

column(width=10,
tags$div(
tags$ul(
tags$li("Manhattan plot of CpGs located within genes"),
tags$li("Annotations (UCSC Genes, ENSEMBL genes, and ",
"transcripts, chromatin states, CpG islands)"),
tags$li("Download summary statistics (odds ratio, effect ",
"estimate, pValues) of CpGs and DMRs in recent AD ",
"and aging studies. ")
)
)
)

Yesterday night, the code ran without error. About an hour ago, it ran without error. Then, I had to briefly close Rstudio, and when I reopened it to run the code, I now get the following error:
Error in tags$div : object of type 'closure' is not subsettable
Calls: runApp ... tabItem -> div -> dots_list -> column -> div -> dots_list
Execution halted

I'm not sure what the problem is. Is there a reason why using tags might cause errors, or that the behavior might be inconsistent? Also, is there a way to create bullet points without using tags?

#2

The above code works fine - the problem is elsewhere:

library(shiny)

ui <- fluidPage(
  column(width=10,
         tags$div(
           tags$ul(
             tags$li("Manhattan plot of CpGs located within genes"),
             tags$li("Annotations (UCSC Genes, ENSEMBL genes, and ",
                     "transcripts, chromatin states, CpG islands)"),
             tags$li("Download summary statistics (odds ratio, effect ",
                     "estimate, pValues) of CpGs and DMRs in recent AD ",
                     "and aging studies. ")
           )
         )
  )
)

server <- function(input, output, session) {}

shinyApp(ui, server)
#3

it was probably some sort of namespace collision, possibly due to the order of loading libraries.
with shiny (via htmltools) tags, is a list of named tags, so tags$div gives

function (..., .noWS = NULL, .renderHook = NULL) 
{
    validateNoWS(.noWS)
    contents <- dots_list(...)
    tag("div", contents, .noWS = .noWS, .renderHook = .renderHook)
}
<bytecode: 0x000002c1c40b5db8>
<environment: namespace:htmltools>

if you got an error instead, that implies you aren't looking at that tags but something else instead.
doing

tags

or

str(tags)

might reveal what (if the issue is recurring)