[isabelle-dev] (Re-)introducing set as a type constructor rather than as mere abbreviation

[Alexander Krauss]

On 08/18/2011 02:16 PM, Florian Haftmann wrote:
> * (maybe)
>    >  hide_fact (open) Set.mem_def Set.Collect_def
>    to indicate that something is going on with these

maybe also declare them [no_atp], to avoid sledgehammer-generated proofs 
that we know are going to break one release later...?

Alex