{% macro redact(topSecret) %}

    {% set length = topSecret|length - 4 %}

    {{ topSecret|slice(0, 3) }}{% for i in 0..length %}*{% endfor %}

{% endmacro %}

​

{# You have to import from _self if the macro is declared in the same file. #}

{% import _self as sharpie %}

​

{{ sharpie.redact('Top secret information') }}

{# => Top******************* #}