[isabelle-dev] (Re-)introducing set as a type constructor rather than as mere abbreviation
nipkow at in.tum.de
Fri Aug 12 14:16:06 CEST 2011
Surely we want to maintain both inductive and inductive_set?
Am 12/08/2011 13:01, schrieb Lawrence Paulson:
> It's clear that for inductive definitions, relations are frequently more
> natural than sets. But I wonder whether a less drastic solution could
> have been found than abandoning sets altogether. (I'm trying to imagine
> some sort of magic operator to ease the transition between sets with
> various forms of tupling and relations.) I certainly find the new world
> confusing. And of course every set has a function type, which has
> implications for all the theorem proving tools.
> On 12 Aug 2011, at 10:26, Alexander Krauss wrote:
>> In 2007, Stefan reengineered the inductive package, which could only
>> define inductive sets at the time. For many applications, inductive
>> predicates were more natural, in particular since one could directly
>> attach mixfix notation to them, without having to introduce another
>> abbreviation. This was a big improvement.
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