ember-named-blocks-polyfill

This addon provides a polyfill for the Yieldable Named Blocks feature. On Ember.js versions with native support for the feature (3.25+), this addon is inert.

Compatibility

• Ember.js v3.12.4 or above
• Ember CLI v2.13 or above
• Node.js v10 or above

Installation

ember install ember-named-blocks-polyfill

Usage

To pass named blocks to a component:

<FancyList @items={{@model}}>
  <:header>This list is <em>fancy</em>!</:header>
  <:row as |item|>
    {{#if item.isHotTip}}
      <h2>Hot Tip&trade;</h2>
      <p>{{item}}</p>
    {{/if}}
  </:row>
</FancyList>

To yield to named blocks:

<header class="fancy-list-header">
  {{yield to="header"}}
</header>

<ul>
  {{#each @items as |item|}}
    <li>{{yield item to="row"}}</li>
  {{/each}}
</ul>

{{#if (has-block "footer")}}
  {{yield to="footer"}}
{{else}}
  <footer>Powered by &lt;FancyList&gt;</footer>
{{/if}}

See the RFC for more information on the named blocks feature.

Limitations

This addon aims to be a high fidelity polyfill both in syntax and semantics. However, there are some minor limitations:

• It is not currently possible to pass an <:else> or <:inverse> named block. See #1.

• When passing only named blocks (without passing a <:default> block) to an addon component whose template was not preprocessed by this polyfill, {{has-block}} in that component's template will return true.

  This is unlikely to be an issue in practice – if you are running an Ember version that requires this polyfill and the addon itself is not also using the polyfill, it problably means that the addon component you are invoking does not accept named blocks anyway, so there is no use in passing them.

  See #4.

Contributing

See the Contributing guide for details.

License

This project is licensed under the MIT License.