如何返回Elm中的元素列表

Question

我正在尝试从ELM中的简单数组构建元素列表.预期的结果实际上只是一个元素列表,其中1作为第一项,2作为第二项,依此类推.

import Html exposing (..)
import Html.Attributes exposing (class, id)
import List exposing (map)

theArray = [1,2,3,4,5,6]

createListItem item =
  li [] [ text (toString item)]

buildList collection =
  map createListItem collection

builtList = ul [] [(buildList theArray)]

main = 
  builtList

但我一直在第13行得到编译器错误.我尝试过将地图元素注释为html,但我看不出应该怎么做.

The 2nd argument to function `ul` is causing a mismatch.

 *13| builtList = ul [] [(buildList theArray)]*

Function `ul` is expecting the 2nd argument to be:

    List VirtualDom.Node

But it is:

    List (List Html)

Answer 1

buildList已经返回了一个类型的值List Html,所以你不需要括号(buildList theArray).将第13行更改为:

builtList = ul [] (buildList theArray)