decode json to html

decode_json_to_html.elm

import Html exposing (..)
import Debug exposing (..)
import List exposing (..)
import Json.Decode exposing (..)


jsonStr : String
jsonStr = """
[
  {
    "title" : "讓廣告盯上消費者",
    "summary" : "  夢想兩個字",
    "date" : 1451836800
  },
  {
    "title" : "日本に上陸「人工知能のスター」",
    "summary" : "人工知能は人間の行動を予測し",
    "date" : 1455897600
  }
]
"""

main = 
  let 
    articleDecoder = list(object3 (,,) ("summary" := string) ("title" := string) ("date" := int))
    pressList: Result String (List ( String, String, Int ))
    pressList = decodeString articleDecoder jsonStr   
  in         
    case pressList of 
      Result.Ok v ->
      let
        htmlList = v 
        |> List.map (\(summary, _, _) -> summary)
        |> List.map Html.text
      in
        Html.div []
          htmlList
          
      Result.Err err ->
        Html.text "Error"  

updater.elm

import Html exposing (..)
import Debug exposing (..)
import String exposing (..)

type alias Bar = 
  {
    a: String
  , b: String
  }
  

type alias Foo = 
  {
    bar : Bar
  }

bar: Bar
bar = 
  {
    a = "A"
  , b = "B"
  }

foo: Foo
foo = 
  {  
    bar = bar
  }


doubleChar: String -> String 
doubleChar a = String.repeat 2 a

tripleChar: String -> String 
tripleChar a = String.repeat 3 a

updateBarA: ( String -> String ) -> Bar -> Bar
updateBarA f bar = 
  { bar | a = ( f bar.a ) }

updateBarB: ( String -> String ) -> Bar -> Bar
updateBarB f bar = 
  { bar | b = ( f bar.b ) }


updateFooBar: (Bar -> Bar ) -> Foo -> Foo
updateFooBar f foo =
  { foo | bar = ( f foo.bar ) }


updateBarATriple = updateBarA tripleChar
updateBarBDouble = updateBarB doubleChar
  
main = 
  let      
    newfoo = 
      foo 
        |> updateFooBar updateBarATriple 
        |> updateFooBar updateBarBDouble 
  in
    div []
    [
      text newfoo.bar.a
    , text newfoo.bar.b    
    ]