The file algebra/domain.spad.pamphlet contains this definition:
  )abbrev domain CATEGORY Category
  ++ Author: Gabriel Dos Reis
  ++ Date Create: February 16, 2008.
  ++ Date Last Updated: February 16, 2008.
  ++ Basic Operations: coerce
  ...


but OpenAxiom does not always treat Category this way:






... --Bill Page,  Wed, 28 May 2008 17:13:05 -0700 reply
Axiom Version:  => /usr/local/lib/open-axiom/x86_64-unknown-linux/1.2.0-2008-05-25 

category regression --gdr,  Wed, 28 May 2008 17:55:47 -0700 reply
hat is a regression, because the rest of the compiler and interpreter
assumes that Category is conceptually a category -- even when it has a
domain implementation.

what? --Bill Page,  Wed, 28 May 2008 18:39:35 -0700 reply
gdr wrote:
  Category is conceptually a category -- even when it has a domain implementation


Could you please explain what that means? :-)
... --gdr,  Wed, 28 May 2008 20:48:32 -0700 reply
At the conceptual level, OpenAxiom thinks of Category as a category.  The
category of categories.  However, it has a domain implementation, e.g.
as reported by )show.  That is just an implementation detail.

domains belong to Category --gdr,  Wed, 28 May 2008 22:06:22 -0700 reply
OpenAxiom trunk as of 2008-05-29 says this:
 (5) -> Category has Category

   (5)  true
                             Type: Boolean

 (6) -> Domain has Category

   (6)  true
                             Type: Boolean

 (7) -> Category has Type

   (7)  true
                             Type: Boolean
</pre>
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