Directive:-declare.md

Use a declare tag to create named variables within a block scope. This is analogous to a variable declaration in Dart.

This Dart code:

var one = 1, two = 2, three = null;

Becomes this Jael:

<declare one=1 two=2 three>
 // Scoped content...
</declare>

Another example (this is actually the test for declare functionality):

<div>
 <declare one=1 two=2 three=3>
   <ul>
    <li>{{one}}</li>
    <li>{{two}}</li>
    <li>{{three}}</li>
   </ul>
   <ul>
    <declare three=4>
      <li>{{one}}</li>
      <li>{{two}}</li>
      <li>{{three}}</li>
    </declare>
   </ul>
 </declare>
</div>

Which yields:

<div>
  <ul>
    <li>
      1
    </li>
    <li>
      2
    </li>
    <li>
      3
    </li>
  </ul>
  <ul>
    <li>
      1
    </li>
    <li>
      2
    </li>
    <li>
      4
    </li>
  </ul>
</div>