layoutz

Zero-dependency library for terminal animations, compositional ANSI strings, plots, and Elm-style TUIs. In Scala, Haskell, and OCaml.

scala haskell ocaml

import layoutz._

val demo = layout(
  row(
    "Layoutz".style(Style.Bold),
    underline("^", Color.Cyan)("DEMO")
  ).center(),
  br,
  row(
    statusCard("Users", "1.2K"),
    statusCard("API", "UP").border(Border.Double),
    statusCard("CPU", "23%").border(Border.Thick).color(Color.Red),
    table(
      Seq("Name", "Role", "Skills"),
      Seq(
        Seq("Gegard", "Pugilist",
          ul("Armenian", ul("bad", ul("man")))),
        Seq("Eve", "QA", "Testing")
      )
    ).border(Border.Round).style(Style.Reverse)
  )
)

demo.putStrLn

import Layoutz

demo = layout
  [ center $ row
      [ withStyle StyleBold $ text "Layoutz"
      , underlineColored "^" ColorCyan $ text "DEMO"
      ]
  , br
  , row
      [ statusCard "Users" "1.2K"
      , withBorder BorderDouble $ statusCard "API" "UP"
      , withColor ColorRed $ withBorder BorderThick $
          statusCard "CPU" "23%"
      , withStyle StyleReverse $ withBorder BorderRound $
          table ["Name", "Role", "Skills"]
            [ [text "Gegard", text "Pugilist",
               ul [text "Armenian",
                   ul [text "bad", ul [text "man"]]]]
            , [text "Eve", text "QA", text "Testing"]
            ]
      ]
  ]

main = putStrLn $ render demo

open Layoutz

let demo =
  layout
    [ center
        (row
           [ s "Layoutz" |> styleBold
           ; underlineColored ~char:"^" ~color:Color.cyan (s "DEMO")
           ])
    ; br
    ; row
        [ statusCard ~label:(s "Users") ~content:(s "1.2K")
        ; statusCard ~label:(s "API") ~content:(s "UP") |> borderDouble
        ; statusCard ~label:(s "CPU") ~content:(s "23%")
          |> borderThick |> colorRed
        ; table
            ~headers:[ s "Name"; s "Role"; s "Skills" ]
            [ [ s "Gegard"; s "Pugilist"
              ; ul [ li ~c:[ li ~c:[ li (s "man") ]
                  (s "bad") ] (s "Armenian") ] ]
            ; [ s "Eve"; s "QA"; s "Testing" ] ]
          |> borderRound |> styleReverse
        ]
    ]

let () = print demo

Showcase

src: scala | haskell | ocaml

Inline animations

src: scala | haskell | ocaml

Interactive TUIs

scala haskell ocaml

import layoutz._

object CounterApp extends LayoutzApp[Int, String] {
  def init = (0, Cmd.none)

  def update(msg: String, count: Int) = msg match {
    case "inc" => (count + 1, Cmd.none)
    case "dec" => (count - 1, Cmd.none)
    case _     => (count, Cmd.none)
  }

  def subscriptions(count: Int) =
    Sub.onKeyPress {
      case Key.Char('+') => Some("inc")
      case Key.Char('-') => Some("dec")
      case _             => None
    }

  def view(count: Int) = layout(
    section("Counter")(s"Count: $count"),
    br,
    ul("Press `+` or `-`")
  )

}

CounterApp.run

import Layoutz

data CounterMsg = Inc | Dec

counterApp :: LayoutzApp Int CounterMsg
counterApp = LayoutzApp
  { appInit = (0, CmdNone)

  , appUpdate = \msg count -> case msg of
      Inc -> (count + 1, CmdNone)
      Dec -> (count - 1, CmdNone)

  , appSubscriptions = \_state ->
      subKeyPress $ \key -> case key of
        KeyChar '+' -> Just Inc
        KeyChar '-' -> Just Dec
        _           -> Nothing

  , appView = \count ->
      layout
        [ section "Counter" [text $ "Count: " <> show count]
        , br
        , ul ["Press '+' or '-'", "Press ESC to quit"]
        ]
  }

main = runApp counterApp

open Layoutz

type msg = Inc | Dec

let () =
  run_app
    { init = (0, CmdNone);
      update =
        (fun msg count ->
          match msg with
          | Inc -> (count + 1, CmdNone)
          | Dec -> (count - 1, CmdNone));
      subscriptions =
        (fun _ ->
          sub_key_press (fun key ->
            match key with
            | KeyChar '+' -> Some Inc
            | KeyChar '-' -> Some Dec
            | _ -> None));
      view =
        (fun count ->
          layout
            [ section ~title:"Counter"
                [ s ("Count: " ^ string_of_int count) ];
              br;
              ul [ li (s "Press `+` or `-`") ]
            ]);
    }

Links

GitHub

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