Maps in Public Interfaces Considered Harmful

Hi,

I'm new to this group, and don't mean to start a flame war with this
somewhat provocative subject line.

But I've been working on a complex domain model that will be available
as part of a runtime framework.  Some of the developers working on this
have prototyped public interfaces that return maps, or dictionaries. 
I've instinctively avoided using maps in public APIs, and have recently
had to examine my reasons for this more closely, for discussion within
the team.

In thinking through this, I'm increasingly of the opinion that maps
shouldn't be regarded as first-class modeling abstractions, and in most
cases shouldn't be exposed through public APIs.  Before I get to the
reasons for this, I'm looking for some pointers from the DDD community
to past discussions, blog entries, references, etc.   I did a cursory
search of this mail group and a a few google searches, but didn't come
up with much.

Is this something that has been discussed or addressed in DDD, modeling
or API design literature?  Any background information would be much
appreciated.

Thanks and Best Regards,

  - Ted Epstein

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