Add Newlines to Output from Groovy StreamingMarkupBuilder

I am creating a massive xml file in Groovy. I'm using StreamingMarkupBuilder because the regular MarkupBuilder runs me out of Java heap space. I'm looking for a way to insert newlines in the StreamingMarkupBuilder or to parse the stream as it is created. I can't write the entire stream to a variable, it's too big. Here's an approximation of what I'm doing:

<FileWriter I created earlier> << new StreamingMarkupBuilder().bind {
    Root {
        Person()
        ID(idVar)
        Location(locationMethod())
        }
    }

Let me know if you have any clarification questions, I'm happy to work with you.

Taking some time off helped me figure out a solution. I am placing mkp.yield "\r\n" between elements like this:

Root {
    mkp.yield "\r\n"
    Person()
    mkp.yield "\r\n"
    ID(idVar)
    mkp.yield "\r\n"
    Location(locationMethod())
    mkp.yield "\r\n"
    }

Not pretty, but it's doing what I need.