Support for recursive partials

[deuill]

Mustache supposedly allows for recursive partials, which are useful for rendering nested/heirarchical data like trees and lists etc.

I think this might be somewhat hard to accomplish due to the fact we compile/parse the template before we render it, so partials are evaluated even if they're wrapped in sections which are empty.

Is there some way around this? Any planned support?

[abh]

Is it in the mustache spec (does hogan.js or the ruby mustache library have this feature)?

[hoisie]

I must admit recursive partials do seem a bit strange to me, but I can imagine a use case.

[deuill]

It's supported in the canonical Ruby implementation, which has a test case for recursive partials. They're useful for data structures with arbitrary depths, such as category lists etc, and help keep the code clean. For example:

category.mustache

<div class="category">
  <div class="name">{{name}}</div>
  {{#sub}}
  {{> category}}
  {{/sub}}
</div>

data.json

[
    {
        "name": "Birds",
        "sub": [
            {
                "name": "Corvidae",
                "sub": [
                    {
                        "name": "Crows"
                    },
                    {
                        "name": "Ravens"
                    },
                    {
                        "name": "Rooks"
                    }
                ]
            },
            {
                "name": "Chickens"
            }
        ]
    },
    {
        "name": "People"
    }
]

The above example would be much dirtier and would not cover all test cases if not for recursive partials. I guess one solution would be to parse each partial seperately during compilation and inserting them conditionally in the rendering phase.

[hoisie]

Nice example @thoughtmonster ! This should definitely be supported. The parsing is recursive, so there might be a quick solution if can some how mark partials as already visited.