[[!comment format=mdwn
 username="joey"
 subject="""comment 2"""
 date="2017-05-06T01:34:39Z"
 content="""
Thanks for that review. That would indeed be bad. To avoid that
potential problem, I've specialized the instance to 
`Hashable (Maybe Hash)`, which is the only Maybe value that currently
needs to be hashed.
"""]]