用参数调用Twig块

I am kinda new to Symfony and Twig. I am trying to override default Twig form template in vendor\symfony\symfony\src\Symfony\Bridge\Twig\Resources\views\Form\form_div_layout.html.twig (Symfony 3.2.6)

As far as I know, block can be defined and then used in other part of template

{% block fooBlock %}
// the block body
{% endblock %}

When parameters are to be passed into, a macro should be rather used

{% macro barMarco(param1, param2, param3) %}
// macro body using param1, param2, param3 etc,
{% endmacro %}

In mentioned above file i found something like. this The definition of block:

{%- block form_errors -%}
    {%- if errors|length > 0 -%}
    <ul>
        {%- for error in errors -%}
            <li>{{ error.message }}</li>
        {%- endfor -%}
    </ul>
    {%- endif -%}
{%- endblock form_errors -%}

And usage:

{%- block form_row -%}
    <div>
        {{- form_label(form) -}}
        {{- form_errors(form) -}}
        {{- form_widget(form) -}}
    </div>
{%- endblock form_row -%}

And here's the question: why this block it called with param (form). I thought a macro should be invoked like this?