Avoiding unsafe

Main.purs

module Main where

import Prelude

import Data.Maybe (Maybe, maybe)
import Data.Traversable (traverse)
import Debug (spy)
import Effect (Effect)
import Effect.Exception (throw)
import Web.DOM.Element (getAttribute, toNode)
import Web.DOM.Element as Element
import Web.DOM.Node (parentElement)
import Web.DOM.NodeList as NodeList
import Web.DOM.ParentNode (QuerySelector(..), querySelector, querySelectorAll)
import Web.HTML (window)
import Web.HTML.HTMLDocument as HTMLDocument
import Web.HTML.Window (document)

mob :: forall a. Effect (Maybe a) -> Effect a
mob e = e >>= maybe (throw "Could not get element") pure

mob' :: forall a. Maybe a -> Effect a
mob' e = mob (pure e)

main :: Effect Unit
main = do
  datas <-
    window
      >>= document
      <#> HTMLDocument.toParentNode
      >>= (querySelectorAll $ QuerySelector "[data-kategoria]")
      >>= NodeList.toArray
      >>= traverse \e -> do
          cellElement <-
            e
              # parentElement
              # mob
              <#> toNode
              >>= parentElement
              # mob
              <#> toNode
              >>= parentElement
              # mob
              <#> Element.toParentNode
          ado
            textElement <-
              cellElement
                # (querySelector $ QuerySelector ".food-etlap-szoveg")
                # mob
            kategoria <-
              e
                # Element.fromNode
                # mob'
                >>= getAttribute "data-kategoria"
                # mob
            datum <-
              e
                # Element.fromNode
                # mob'
                >>= getAttribute "data-datum"
                # mob
            ar <-
              cellElement
                # (querySelector $ QuerySelector ".price")
                # mob
                <#> Element.toParentNode
                >>= (querySelector $ QuerySelector ".center")
                # mob
            in { textElement, kategoria, datum, ar }
  let
    _ = spy "" datas
  pure unit