Pass a template string to a Jinja macro

Question

I want to render a template string from a macro. I tried to do it with the following macro that renders the template using {{ comment|safe }}, but variables in the template such as {{ name }} are rendered literally instead of with the value of name. How can I allow variable data in a macro argument?

{% macro comment_el(image_url, name, comment) %}
  <div class="media no-border-top">
    <div class="media-left">
      <a href="{{ outgoing_url }}" >
        <img class="media-object" src="{{ image_url }}" />
      </a>
    </div>
    <div class="media-body">
      <h4 class="media-heading"><a href="{{ outgoing_url }}" >{{ name }}</a></h4>
      <p>{{ comment|safe }}</p>
    </div>
  </div>
{% endmacro %}

{{ comment_el(
    url_for("static", filename="img/c01.jpg"),
    "Some Name",
    "This comment is amazing. All I want to say is that {{ name }} is an amazing person"
) }}

Output:

<p>This comment is amazing. All I want to say is that {{ name }} is an amazing person</p>

Answer 1

That's not possible.

However, you can have a caller in Jinja macros that lets you pass a block:

{% macro comment_el(image_url, name) %}
    ...
    <div class="media-body">
      <p>{{ caller() }}</p>
    </div>
    ...
{% endmacro %}

Then call it like this:

{% call comment_el(url_for("static", filename="img/c01.jpg"), "Some Name") -%}
    This comment is amazing. All I want to say is that {{ name }} is an amazing person 
{%- endcall %}

Relevant docs: http://jinja.pocoo.org/docs/2.9/templates/#call

---

Another option to solve it would be this:

{% set comment -%}
    This comment is amazing. All I want to say is that {{ name }} is an amazing person
{%- endset %}
{{ comment_el(url_for("static", filename="img/c01.jpg"),
    "Some Name",
    comment
) }}

Relevant docs: http://jinja.pocoo.org/docs/2.9/templates/#block-assignments

---

For the sake of completeness, you could also use formatting:

{{ comment_el(url_for("static", filename="img/c01.jpg"),
"Some Name",
"This comment is amazing. All I want to say is that %s is an amazing person" | format(name)
) }}