Autosuggest with caching in Elm

autosuggest.elm

import Dict exposing (Dict)
import Html exposing (Html, div, text, input, ul, li)
import Html.App as Html
import Html.Events exposing (..)
import Task exposing (Task)
import String

---------------------------

main = 
  Html.program
    { init = init
    , view = view viewSuggestion
    , update = update getSuggestions
    , subscriptions = subscriptions
    }

---------------------------

data : List String
data = 
  [ "Arizona"
  , "Arkansas"
  , "California"
  , "Colorado"
  , "Delaware"
  , "Florida"
  , "New York"
  , "New Jersey"
  , "Pennsylvania"
  , "Texas" ]

getSuggestions : String -> Task String (List String)
getSuggestions query = 
  if String.trim query == "" then Task.fail "No Query" else 
  data
  |> List.filter (String.startsWith query)
  |> Task.succeed
  

---------------------------

type alias Model suggestion = 
  { cache : Dict String (List suggestion) 
  , query : String 
  }
  

type Msg suggestion
  = Query String
  | AddSuggestions String (List suggestion)
  | NoOp



init : (Model suggestion, Cmd (Msg suggestion))
init = 
  ( { cache = Dict.empty
    , query = ""
    }
  , Cmd.none )
  
  
subscriptions : Model suggestion -> Sub (Msg suggestion)
subscriptions model =
  Sub.none  
  
  
update : (String -> Task error (List suggestion)) 
      -> Msg suggestion 
      -> Model suggestion 
      -> (Model suggestion, Cmd (Msg suggestion))
update getSuggestions msg model = 
  case msg of 
    Query query -> 
      let cmd = 
        Task.perform (always NoOp) (AddSuggestions query) (getSuggestions query)
      in 
        ( { model | query = query }
        , cmd )
    
    AddSuggestions query suggestions -> 
      ( { model | cache = Dict.insert query suggestions model.cache }
      , Cmd.none )
      
    NoOp -> 
      ( model
      , Cmd.none )
      

view : (suggestion -> Html (Msg suggestion)) -> Model suggestion -> Html (Msg suggestion)
view viewSuggestion model = 
  let suggestions = 
        case Dict.get model.query model.cache of 
          Nothing ->
            []
          Just results -> 
            results
  
  in
    div 
      []
      [ input 
          [ onInput Query ] 
          [ ]
       
      , div 
          []
          ( List.map viewSuggestion suggestions ) ]
          
          
viewSuggestion : String -> Html a
viewSuggestion suggestion = 
  div 
    []
    [ text suggestion ]