R相当于python星解包？

Question

I have a routine in R that takes a variable number of arguments, and I need to call this routine passing an unpacked list. In python I would do

lst = [1,2,3]
my_func(*lst)

What is the equivalent syntax in R?

To be more specific, I am using shiny and I am trying to create a dynamic list of entries

This is the code.

server <- function(input, output) {
  applist <- c(
      a(href="#", class="list-group-item", 
        h4(class="list-group-item-heading", "Entry 1"),
        p(class="list-group-item-text", "Description")
      ),
      a(href="#", class="list-group-item", 
        h4(class="list-group-item-heading", "Entry 2"),
        p(class="list-group-item-text", "Description")
      ))
   
  output$applist = renderUI(
    div(class="list-group", ... applist)
  )
}

Answer 1

Posted by OP.

Here is how I solved. using do.call does the trick, but you have to be aware that lists in python is not the same as lists in R. A list in R is more similar to a mix of a dictionary and a list.

  applist <- list(
      class="list-group",
      a(href="#", class="list-group-item"),
      a(href="#", class="list-group-item")
  )

  output$applist = renderUI(do.call(div, applist))

Note how the applist contains both a named entry class and non-named entries. As I said, hybrid. The do.call then does the "unpacking", but the content of applist is then distributed as named or non-named argument. It works differently from python, where named and non-named are always separated.