Iterating over a map in Elm

DictIterators.elm

{--
  Some Elm code for various ways to iterate over a map
  
  Run at http://elm-lang.org:1234/try
--}

import Html exposing (text, div, br)
import Dict exposing (Dict)
import String exposing (toUpper)

initial = Dict.fromList [(1, "one"), (2, "two")]

foldToString = Dict.foldl (
    \k v acc -> acc ++ "<" ++ (toString k) ++ "|" ++ v ++ ">"
  ) "" initial

mapToDict = Dict.map (
    \k v -> (toUpper) v
  ) initial
  
foldToList = Dict.foldl (
    \k v acc -> ((toString k) ++ ": " ++ v) :: acc
  ) [] initial

main = div [] [
  "initial: " ++ toString initial |> text, br[][],
  "foldToString: " ++ toString foldToString |> text, br[][],
  "mapToDict: " ++ toString mapToDict |> text, br[][],
  "foldToList: " ++ toString foldToList |> text, br[][]
  ]

{--
  Should see the following output:
  
  initial: Dict.fromList [(1,"one"),(2,"two")]
  foldToString: "<1|one><2|two>"
  mapToDict: Dict.fromList [(1,"ONE"),(2,"TWO")]
  foldToList: ["2: two","1: one"]
--}