title: List all available font awesome icons for Leaflet map in Shiny, R
body: <p>I'm makin a Shiny App where I want the user to be able choose the Font Awesome icon that goes into an Awesome Marker.</p>
  
  <p>Here's a simple app that lets the user choose the marker colour, the icon colour and the icon (name).</p>
  
  <pre><code>library(shiny)
  library(leaflet)
  
  icon_names &lt;- c("home", "map-pin")
  
  marker_colours &lt;- list(Standard = c('red', 'orange', 'beige', 'green', 'blue', 'purple', 
                                      'pink', 'cadetblue', 'white', 'grey', 'black'),
                         Shades   = c('darkred', 'lightred', 'darkgreen', 'lightgreen', 
                                      'darkblue', 'lightblue', 'darkpurple', 'lightgray'))
  
  
  server &lt;- function(input, output) {
  
    output$map &lt;- renderLeaflet({
  
      icons &lt;- awesomeIcons(
        icon        = input$icon,
        iconColor   = input$icon_colour,
        library     = 'fa',
        markerColor = input$marker_colour
      )
  
      leaflet() %&gt;% 
        addTiles() %&gt;% 
        addAwesomeMarkers(lng            = 4.9, 
                          lat            = 52.38,
                          icon           = icons
        )
    })
  }
  
  ui &lt;- fluidPage(
    sidebarLayout(
      sidebarPanel(
        selectInput("icon", "Icon:", 
                    choices = icon_names, selected = "home"),
        selectInput("marker_colour", "Marker colour:", 
                    choices = marker_colours, selected = "red"),
        selectInput("icon_colour", "Icon colour:", 
                    choices = c("#ffffff", "#000000"), selected = "#ffffff")
      ),
      mainPanel(leafletOutput("map"))
    )
  )
  
  shinyApp(ui = ui, server = server)
  </code></pre>
  
  <p>But now I want a way to access all the possible FA icons available in the R package Leaflet. </p>
  
  <p>So the bit of code </p>
  
  <pre><code>icon_names &lt;- c("home", "map-pin")
  </code></pre>
  
  <p>should change to something that would result in a string with all available icons.</p>
  
  <p>Your advice is much appreciated!</p>
  
  <p>Best,
  Jiddu</p>