Your pseudo XML seems quite broken, since the supposed git style doesn't close the parent at all.
But the git directory entry contains:
* a type (this one is quite limited, so I'm not sure how well that could be (ab)used
* a name
* a pointer to the content
But the git directory entry contains: * a type (this one is quite limited, so I'm not sure how well that could be (ab)used * a name * a pointer to the content
Which is exaclty what an AST entry has.