Opa now provides support for translation by means of the @i18n directive. We can put a translation function inside the @i18n directive, and it will be replaced by a proper value according to different languages. An example is worth a thousand words, so let's get started with a simple example:
import stdlib.web.client
hello = function {
case "en": "Hello"
case "fr": "Bonjour"
case "zh": "你好"
default: "Hi"
}
function page(){
<h1> {@i18n(hello)} </h1>
<input type="button" value="English" onclick={set_lang("en")}/>
<input type="button" value="French" onclick={set_lang("fr")}/>
<input type="button" value="Chinese" onclick={set_lang("zh")}/>
}
function set_lang(lang)(_){
I18n.set_lang(lang)
Client.reload()
}
Server.start(Server.http, {title:"Opa Packt", ~page})Save this code into a file, 801.opa, then compile and run it with the following command:
opa 801.opa --
The result looks as shown in the following screenshot:
The page shows...