Lambdas with "partial" partial evaluation

[marccelani]

I have a partial..

partial.mustache

---

{{!...includes other things, but for simplicity...}}
{{! OptionalMarker}}

And an outer context which has a lambda...

{"ReplaceOptionalMarkers", mstch::lambda([](const std::string& text) -> mstch::node {
    auto result = text;
    boost::replace_all(result, "{{! OptionalMarker}}", "Rendered Optional!");
    return result;
  })}

I want to be able to do something like...

complete.mustache

---

{{#context:ReplaceOptionalMarkers}}{{> partial}}{{/context:ReplaceOptionalMarkers}}

Ideally, this would work even if partial includes other partials, and the marker is in those dependencies.

The feature I am asking for is to have a lambda function which "partially" realizes the partial. Rather than fully rendering the partial (which would lose the comment markers), it would replace the {{> partial}} in the string passed to the lambda with whatever is actually within partial, and recursively do so. User will need to avoid infinite loops.

The only alternative way I can imagine implementing something like this is by using global state and objects, which feels like the wrong pattern.

[marccelani]

handlebars also does this better, because they support passing parameters to partials.