Can I use a Mustache var in a partial name?

I currently use a template for multiple pages (basic.mustache) and everything work great, but I want to add different boxes (box1.mustache, box2.mustache) in a sidebar depending of the page.

Basically, I would need to add the mustache templates in the object parsed by the template.

{
  title: "My page tile",
  content: ...
  sidebar: [
    "box1.mustache",
    "box2.mustache"
  ]
}

but how can I do something equivalent to this in the main template (basic.mustache) ?

{{#sidebar}}
  {{>.}}
{{/sidebar}}

Solution

No, it's not possible to do like that. But it's still possible to accomplish what you're looking for. See this answer for one answer.

Looking at your example, though, I think what you're looking for is better addressed by template inheritance (the BLOCKS pragma).

So you'd have layout.mustache as your "parent" template:

<!DOCTYPE html>
<html>
  <head>
    <title>{{$ title }}My site has a title!{{/ title }}</title>
  </head>
  <body>
    <section id="main">
      {{$ content }}{{/ content }}
    </section>
    <section id="sidebar">
      {{$ sidebar }}{{/ sidebar }}
    </section>
  </body>
</html>

And my_page.mustache as your "page" template:

{{< layout }}

  {{$ title }}This page has its own title!{{/ title }}

  {{$ sidebar }}
    {{> box1 }}
    {{> box2 }}
  {{/ sidebar }}

  {{$ content }}
    Here's all your awesome content!
  {{/ content }}

{{/ layout }}

Notice how my_page loads box1 and box2 partials into the {{$ sidebar }} block. You could even have default sidebar partials by adding them to the {{$ sidebar }} block in the main layout (just like there's a default {{$ title }}).

Note that BLOCKS is a pragma, and as such is not enabled by default in Mustache.php. To use it, you either have to add {{% BLOCKS }} to the first line of any template with blocks in it, or pass ['pragmas' => [Mustache_Engine::PRAGMA_BLOCKS]] to the Mustache_Engine constructor to enable them globally.