Jade Templates - Dynamically Calling a Mixin

Question

How can I use a string from the json being fed into a Jade template to dynamically load a mixin? Below, the goal is for twoColumn.jade to load the foo and bar mixins.

twoColumn.jade

mixin twoColumns(obj)
    .container-fluid
        .row(class=obj.class)
            for item in obj.items
                .col-xs-12.col-sm-3
                    //- Syntax for dynamically calling a mixin?
                    +item.template(item)

content.json

{
    "twoColumns": {
        "class": "foobar",
        "items": [
            {
                "template": "foo",
                "title": "Hello"     
            },
            {
                "template": "bar",
                "title": "World"     
            }
        ]            
    }
}

Answer 1

This is a feature that is not very obvious in Jade, as it is not explicitly mentioned in the documentation. You can actually use the interpolation syntax (#{...}) for dynamically choosing the mixin name.

From the Jade language guide:

interpolation? yup! both types of text can utilize interpolation, if we passed { name: 'tj', email: '[email protected]' } to the compiled function we can do the following:

#user #{name} <#{email}>

outputs <div id="user">tj &lt;[email protected]&gt;</div>

Example usage:

mixin foo(item)
  p Foo called

mixin bar(item)
  p Bar called

mixin twoColumns(obj)
  .container-fluid
    .row(class=obj.class)
      for item in obj.items
        .col-xs-12.col-sm-3
          +#{item.template}(item)