purescript-chameleon

In which framework should I write my PureScript web app? They differ in many aspects like state management, virtual DOM implementation or native solution or JS-bindings? Many difficult questions, many pros and cons.

I'd argue that for a large part of the apps this does not matter. Just write your pure views in a framework agnostic way with this library. And you can integrate it in any framework that does provide a matching implementation.

Currently available implementations:

• halogen
• react-basic

With this library web views are written in tagless final style. Instead of returning a concrete type like HTML Msg they return html Msg, along with the constraint Html html. This is analogous to writing monadic code like Monad m => .... -> m Unit.

module Test.SampleReadme where

import Prelude

import Chameleon as VD

type State = Int

data Msg
  = Increment Int
  | Decrement Int

update :: Msg -> State -> State
update msg state = case msg of
  Increment n -> state + n
  Decrement n -> state - n

view :: forall html. VD.Html html => { count :: Int } -> html Msg
view props =
  VD.div
    [ VD.style "border: 1px solid red"
    ]
    [ VD.text "Counter"
    , VD.div [] [ VD.text $ show props.count ]
    , VD.button [ VD.onClick (Increment 1) ]
        [ VD.text "+" ]
    , VD.button [ VD.onClick (Decrement 1) ]
        [ VD.text "-" ]
    ]