Edit yield content of an Ember block component before rendering it?

I'd like to edit the content of the yield passed to a block component.

For example, having:

{{#no-foo}}foo{{/no-foo}}

Should output:

<div id="emberxxxx">bar</div>

Because I'd like to have something inside my component logic like this:

init: function() {
  this.set('yield', this.get('yield').replace('foo', 'bar'));
}

Is it something possible with Ember.js?