[[!comment format=mdwn
 username="joey"
 subject="""comment 10"""
 date="2016-03-20T17:29:48Z"
 content="""
The list of child properties is a problem, because it would need to be
`[Property proptypes]` and the proptypes will vary, so heterogenious list.

The proptypes of the child properties needs to influence the proptypes of
the parent anyway. Take intersection of the parent's targets and its
children's targets, plus both's non-target types.

So, could calculate that proptypes, and use it as the type of both the
parent property, and each child property in the list.
"""]]
