How can I indirectly call a macro in a Jinja2 template?

I'm trying to do something like this:

{% macro obj_type_1 %}
stuff
{% endmacro %}
{% macro obj_type_2 %}
stuff
{% endmacro %}

{{ (obj|get_type)(obj) }}

In this example, get_type is a filter that would return obj_type_1 or obj_type_2 -- ie, the name of the macro to call for obj. I don't want to mark up obj with configuration output because right now obj is used in several templates as structural data, to be rendered with different markup depending on the context.

I know the syntax here is a bit tortured, but I think that's because what I want to do isn't immediately possible in Jinja templates. I'm trying to replace a big damn schwack of if/elif/else crap in some config generation code with templates, but this bit seems to be a sticking point.