An ascii progress bar in Elm

ProgressBar.elm

-- | An ascii progress bar.
-- | Should be used with a monospace font.
-- | Renders like this:
-- | 
-- |    [============    ]
-- |
-- | or half steps
-- |
-- |    [======-         ]
-- |

progressBar : Int -> Float -> String
progressBar max p =
    let
        progressAbs =
            p * toFloat max

        left =
            truncate progressAbs

        half =
            (progressAbs - toFloat left) >= 0.5

        leftString =
            List.repeat left "="
                |> String.join ""
                |> (\s ->
                        if half then
                            s ++ "-"

                        else
                            s
                   )

        remaining =
            max - String.length leftString

        filler =
            List.repeat remaining " " |> String.join ""
    in
    "[" ++ leftString ++ filler ++ "]"