Add properties to context when rendering partial in Handlebars.js

Question

Is it possible to add properties to context when rendering a partial template with handlebars.js?

{{> MyTemplate { X: Y }}}

I have a shared template that I need to insert some values to, depending on from which "master" template it is used.

Answer 1

You can't do this directly inside the call to the partial, no. But you can pass context into a partial, provided you already have it available in the wrapping context.

In order to "embed" data in a context, you can use a helper that sets a private variable, like so:

<div>
  {{makeVar 'mode' 33}}
  <span>mode: {{@mode}}</span><!-- will return mode: 33 -->
</div>

Then, by passing something dynamic from context into the makeVar helper, you can compute a value for @mode which will then be added into the current context.

You could also modify the context itself, or merge the context with computed data on the fly. ( Be careful: doing it that way affects downstream users of the context as well.)

So, you could call the partial like this, and let the wrapping context set @mode accordingly.

<div>
  {{> myPartial .}}<!-- inside partial, @mode is accessible, along with context -->
</div>

See: http://jsfiddle.net/mcw0933/Cy64X/