What am I trying to do?

Based on the documentation, this is valid freemarker:

[#macro foo rest...]
  [#-- do something with rest... --]

  <div
    [#list rest as key, val]
      ${key}="${val}"
    [/#list]
  >
  </div>
[/#macro]

I want to be able to create a macro that passes rest... to a child macro (e.g. foo), something like this:

[#macro bar rest...]
  [#-- pass rest... to [@foo /] --]

  [@foo
    [#list rest as key, val]
      ${key}="${val}"
    [/#list]
  /]
[/#macro]

What I tried

Note: The following code snippet does not work, I tested this on https://try.freemarker.apache.org/.

[#macro foo rest...]
  <div
    [#list rest as key, val]
      ${key}="${val}"
    [/#list]
  >
  </div>
[/#macro]

[#macro bar rest...]
  [@foo
    [#list rest as key, val]
      ${key}="${val}"
    [/#list]
  /]
[/#macro]

[@foo a="1" b="2" /]
[@bar c="3" d="4" /]

Expected Output:

<div a="1" b="2"></div>
<div c="3" d="4"></div>