如何以编程方式获取部署地址？(How to get deployed address programmatically?)

 您正在寻找的功能是ports 。 将您的模块声明为port module （即，使用port module替换文件顶部的单词port module ），并声明一个传出端口： 
 
port alert : String -> Cmd msg
 
 这定义了一个Elm函数alert ，它采用String并生成一个命令。 （注意它是一个Cmd msg ，小写的msg ，意味着它实际上不会产生大写-M Msg ; msg是小写的事实表明它是一个类型变量，并且alert "blah"将是可返回的从任何更新函数，无论具体的Msg类型。） 
 
 在JavaScript中，你会写这样的东西： 
 
app.ports.alert.subscribe(function(str) {
    alert(str);
});
 
 该代码“订阅”由Elm代码发送到alert端口的消息 - 不要将此与Elm subscriptions混淆，Elm subscriptions监听发送给 Elm的消息。 
 
 现在，在Elm中，您可以创建alert "Hi there"等命令。 执行时，该命令将调用您在Javascript中定义的函数，从而导致警报显示"Hi there"文本。 
 
 请注意，您不能声明，例如， alertTime : Cmd msg没有参数。 您可以声明alertTime : () -> Cmd msg ，并通过从更新函数返回alertTime ()来使用它。 我相信如果您的Javascript函数接受输入，这将发送值为[]的Javascript。 

The feature you're looking for is ports. Declare your module to be a port module (that is, replace the word module at the top of your file with port module), and declare an outgoing port:
 
port alert : String -> Cmd msg
 
This defines an Elm function alert which takes a String and produces a command. (Note that it is a Cmd msg, lowercase msg, meaning that it doesn't actually ever result in a capital-M Msg; the fact that msg is lowercase indicates that it is a type variable, and alert "blah" will be returnable from any update function, no matter the concrete Msg type.) 
 
In JavaScript, you'd write something like this:
 
app.ports.alert.subscribe(function(str) {
    alert(str);
});
 
That code "subscribes" to messages being sent by the Elm code to the alert port -- don't confuse this with Elm subscriptions, which listen for messages being sent to Elm.
 
Now, in Elm, you can create commands like alert "Hi there". When executed, that command will call the function you defined in Javascript, causing an alert to appear with the text "Hi there".
 
Note that you cannot declare, e.g., alertTime : Cmd msg with no arguments. You can declare alertTime : () -> Cmd msg, and use it by returning alertTime () from your update function. I believe this will send Javascript the value [], if your Javascript function accepts input.