Symfony2, Twig: Better use block or variable?

Question

What solution is better and recommended for short string elements? To define block and let user override it contents like:

<title>{% block title %}{% endblock %}</title>

or make block of variables, set their default values and let user import this block reset variable he want like:

base template:

{% block variables %}
    {% set meta.title = '' %}
{% endblock %}
<title>{{ meta.title }}</title>

user template:

{% block variables %}
    {{ parent() }}
    {% set meta.title = 'some title' %}
{% endblock %}

Answer 1

I'd go with blocks. Also, remember that if you want to output contents of a block more than once, you can use the block function:

<title>{% block title %}{% endblock %}</title>

<h1>{{ block('title') }}</h1>