已更新为Elm 0.18

要公开Comments.Model，请确保您的Comment.elm文件公开所有类型和功能，如下所示:

To expose Comments.Model, make sure your Comments.elm file exposes all types and functions like this:

module Comments exposing (..)

或者，您可以公开如下类型和函数的子集:

Or, you can expose a subset of types and functions like this:

module Comments exposing (Model)

解码器存在一些问题.首先，要匹配您的JSON，您将需要一个记录类型别名，该别名公开一个posts列表帖子.

There are a few problems with your decoders. First off, to match your JSON, you're going to need a record type alias that exposes a single posts list Posts.

type alias PostListContainerModel =
  { posts : List Post.Model }

您没有评论用的解码器.看起来像这样:

You are missing a decoder for comments. That will look like this:

commentDecoder : Decoder Comment.Model
commentDecoder =
  Decode.map2
    Comment.Model
    (Decode.field "text" Decode.string)
    (Decode.field "date" Decode.string)

为了避免歧义，我将把您的decoder函数重命名为postDecoder.现在，您可以使用新的commentDecoder修复comments解码器行.

I'm going to rename your decoder function to postDecoder to avoid ambiguity. Now you can fix the comments decoder line by using the new commentDecoder.

postDecoder : Decoder Post.Model
postDecoder =
  Decode.map5
    Post.Model
    (Decode.field "img" Decode.string)
    (Decode.field "text" Decode.string)
    (Decode.field "source" Decode.string)
    (Decode.field "date" Decode.string)
    (Decode.field "comments" (Decode.list commentDecoder))

最后，我们可以使用先前创建的帖子包装类型(PostListContainerModel)来修复decoderColl:

Lastly, we can fix decoderColl by using that posts wrapper type (PostListContainerModel) we created earlier:

decoderColl : Decoder PostListContainerModel
decoderColl =
  Decode.map
    PostListContainerModel
    (Decode.field "posts" (Decode.list postDecoder))