elm

I am looking for a concise way of updating a nested value inside a record in Elm (0.18). Given the following example: person = { name = "Steven", address = { country = "Spain", city = "Barcelona" } } I can update person.name to "Steve" using the following expression: { person | name = "Steve" } However, I am looking for a way to update a nested value. For instance, I would like to update person.address.city to "Madrid". I tried the following: { person | address.city = "Madrid" } { person | address = { address | city = "Madrid" } } { person | address = { person.address | city = "Madrid" } } The

It's a really basic question but I didn't find any example. I have a view like this : view address model = div [] [ div [] [ text <|"ID : " ++ toString model.id ] , form [] [ input [ value model.title ] [] , textarea [ value model.content ] [] , button [ onClick address ( SubmitPost model ) ] [ text "Submit" ] // Here is the issue, I want to send my updated model ] ] So it display a form with the content inside. So if I write in my input and textarea to update the content, how do I "catch" my updated model on the onClick event on the button to send it? Chad Gilbert The standard way to handle

Coming from react, I am learning to understand Elm. In the Todomvc example code , there is the following code snippet: -- How we update our Model on a given Msg? update : Msg -> Model -> ( Model, Cmd Msg ) update msg model = case msg of NoOp -> model ! [] <-- What is this? What I (think I) understand, is that the update function takes in a msg of type Msg and a model of type Model , and returns a tuple of containing a Model and a Cmd Msg . But how should I read the return statement? model ! [] What does this statement mean? return a "model [something] empty list"? Did I miss something in the

写文章不容易，点个赞呗兄弟 <br> <br> 专注 Vue 源码分享，文章分为白话版和 源码版，白话版助于理解工作原理，源码版助于了解内部详情，让我们一起学习吧 研究基于 Vue版本 【2.5.17】 如果你觉得排版难看，请点击 下面链接 或者 拉到 下面 关注公众号 也可以吧 【Vue原理】Diff - 源码版 之 相关辅助函数 在开始我们的 Diff 主要内容之前，我们先来了解下其中会用的的一些辅助函数 本来可以放到 Diff 那里写，但是全部合起来内容又太多 而且这些函数比较具有公用性，就是抽出来用 所以打算独立一篇文章，先预热一下，内容也不多，也挺简单，光看下也会对我们的思维有所帮助 节点操作函数 下面是 Diff 在比较节点时，更新DOM 会使用到的一些函数 本来会有更多，为了看得方便，我把一些合并了 下面会介绍三个函数 insert，createElm，createChildren 简单介绍 insert 作用是把节点插入到某个位置 createElm 作用是创建DOM 节点 createChildren 作用也是创建DOM 节点，但是处理的是一个数组，并且会创建 DOM 节点 和 文本节点 下面就来仔细说说这三个方法 1 insert 这个函数的作用就是 插入节点 但是插入也会分两种情况 1、没有参考兄弟节点，直接插入父节点的子节点末尾 2、有参考兄弟节点

In recent implementations of Classic FRP, for instance reactive-banana, there are event streams and signals, which are step functions (reactive-banana calls them behaviours but they are nevertheless step functions). I've noticed that Elm only uses signals, and doesn't differentiate between signals and event streams. Also, reactive-banana allows to go from event streams to signals (edited: and it's sort of possible to act on behaviours using reactimate' although it not considered good practice), which kind of means that in theory we could apply all the event stream combinators on signals