1{%- if include.source1 == nil -%}
2  {%- if include.source0 == nil -%}
3    {%- assign __return = include.target -%}
4  {%- else -%}
5    {%- assign __return = include.source0 -%}
6  {%- endif -%}
7{%- else -%}
8  {%- assign __return = include.source1 -%}
9{%- endif -%}