[Run a summary of functions and the associated description from a loaded package] #R

pkg_summary.R

#' Run a summary of functions and the associated description
#' for a loaded package
#' 
#' @param package_name String providing the name of the loaded package, e.g. surveytoolbox
#' 
#' @examples
#' \dontrun{
#' pkg_summary("surveytoolbox")
#' pkg_summary("wpa")
#' pkg_summary("rwa")
#' pkg_summary("sjlabelled")
#' }
#' 
#' @export
generate_summary <- function(package_name){

  pkg_string <- paste0("package:", package_name)

  fnc_names <- lsf.str(pkg_string) %>% as.character()

  generate_fam <- function(fnc_names, package_name = "wpa"){
    fnc_names %>%
      utils::help(eval(package_name)) %>%
      utils:::.getHelpFile() %>%
      purrr::keep(~attr(.x, "Rd_tag") == "\\seealso") %>%
      purrr::map(as.character) %>%
      purrr::flatten_chr() -> p


    if(length(p) == 0){
      return("")
    } else {
      p[[2]] %>% # Extract second element
        str_remove(., "Other ") %>%
        str_remove(., ":") %>%
        str_remove(., "[\n]") %>%
        str_trim()
    }
  }

  generate_desc <- function(fnc_names, package_name = "wpa"){
    fnc_names %>%
      utils::help(eval(package_name)) %>%
      utils:::.getHelpFile() %>%
      purrr::keep(~attr(.x, "Rd_tag") == "\\description") %>%
      purrr::map(as.character) %>%
      purrr::flatten_chr() %>%
      paste0(., collapse="") %>%
      str_remove(., "[\n]") %>%
      str_trim()
  }

  generate_title <- function(fnc_names, package_name = "wpa"){
    fnc_names %>%
      utils::help(eval(package_name)) %>%
      utils:::.getHelpFile() %>%
      purrr::keep(~attr(.x, "Rd_tag") == "\\title") %>%
      purrr::map(as.character) %>%
      purrr::flatten_chr() %>%
      paste0(., collapse="") %>%
      str_remove(., "[\n]") %>%
      str_trim()
  }

  generate_argument <- function(fnc_names, package_name = "wpa"){
    fnc_names %>%
      utils::help(eval(package_name)) %>%
      utils:::.getHelpFile() %>%
      purrr::keep(~attr(.x, "Rd_tag") == "\\arguments") %>%
      purrr::map(as.character) %>%
      purrr::flatten_chr() -> p

    if(length(p) == 0){
      return("")
    } else {
      p %>%
        str_remove_all(., "[\n]") %>%
        .[. != ""] %>% # remove blanks
        str_trim() %>%
        str_remove_all(., "list\\(") %>% # clean up
        str_remove_all(., ",.+") %>% # remove argument description
        str_remove_all(., "[:punct:]") %>% # remove all non-words
        paste(collapse = "; ")
    }
  }

  fnc_fam <-
    fnc_names %>%
    map_chr(generate_fam)

  fnc_title <-
    fnc_names %>%
    map_chr(generate_title)

  fnc_desc <-
    fnc_names %>%
    map_chr(generate_desc)

  fnc_arg <-
    fnc_names %>%
    map_chr(generate_argument)

  tibble(Functions = fnc_names,
         Family = fnc_fam,
         Title = fnc_title,
         Description = fnc_desc,
         Arguments = fnc_arg) %>%
    return()
}