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From: nospam@thanks.com.au (Don Harrison)
Subject: Re: Can't export object of private type
Date: 1999/03/01
Date: 1999-03-01T00:00:00+00:00	[thread overview]
Message-ID: <F7wKy8.4Jq@syd.csa.com.au> (raw)
In-Reply-To: 7b5u87$s88$1@nnrp1.dejanews.com

Robert_dewar wrote:

:In article <F7r2DF.23y@syd.csa.com.au>,
:  nospam@thanks.com.au wrote:
:> Because *non-recursive* declarations imply a partial
:> ordering, a valid elaboration sequence can be determined
:> for them, irrespective of declaration order.
:
:I know that seems reasonable for simple cases, but this
:approach simply will not work, it is recursively
:undecidable in the general case what ordering should be
:used, since it depends on computational paths.

By "computational paths", do you mean:

  - Functions called to initialise package variables, and
  - Procedures called in package blocks?

I may be missing something here, but..

Wouldn't any declarations used in such operations simply be ordered ahead
of the declaration that uses them in the elaboration order? You wouldn't 
need to order the branch declarations WRT each other because, you only 
need a partial ordering, rather than a total one. 

The only problem would seem to be where the ordering dictated by different 
declarations are mutually contradictory. This would yield a compile error. 

:Linear elaboration is a model that enormously simplifies
:the semantics of the language, ..

I can imagine elaboration problems would be even worse without it. Perhaps,
it makes them tolerable.

:(note that you do NOT have a formal definition of what
:you mean by recursive here, and you will find that any
:attempt to formalize this definition will fail.)

  "A recursive declaration is one which is composed of at least 
   one declaration defined (transitively) in terms of the 
   declaration being considered."


-- 
Don (Harrison).   donh at syd.csa.com.au






  parent reply	other threads:[~1999-03-01  0:00 UTC|newest]

Thread overview: 128+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <F7JoCB.JxB@syd.csa.com.au>
1999-02-24  0:00 ` Can't export object of private type Don Harrison
1999-02-24  0:00   ` Tom Moran
1999-02-24  0:00   ` Samuel Mize
1999-02-24  0:00     ` Tucker Taft
1999-02-25  0:00     ` Don Harrison
1999-02-25  0:00       ` Samuel Mize
1999-02-26  0:00         ` Don Harrison
1999-02-27  0:00           ` Nick Roberts
1999-03-01  0:00             ` Don Harrison
1999-03-02  0:00               ` Matthew Heaney
1999-03-01  0:00             ` Don Harrison
1999-03-01  0:00               ` Nick Roberts
1999-03-01  0:00                 ` Don Harrison
1999-03-02  0:00                   ` Matthew Heaney
1999-03-03  0:00                     ` Don Harrison
1999-03-03  0:00                       ` Samuel Mize
1999-03-04  0:00                         ` Don Harrison
1999-03-07  0:00                     ` Ehud Lamm
1999-03-01  0:00               ` Matthew Heaney
1999-03-01  0:00                 ` Nick Roberts
1999-03-03  0:00               ` Robert A Duff
1999-03-04  0:00                 ` Don Harrison
1999-03-04  0:00                   ` Robert A Duff
1999-02-28  0:00         ` Matthew Heaney
1999-03-01  0:00           ` Nick Roberts
1999-03-01  0:00             ` Matthew Heaney
1999-03-01  0:00             ` Matthew Heaney
1999-03-02  0:00               ` Nick Roberts
1999-03-01  0:00           ` Samuel Mize
1999-02-25  0:00       ` fraser
1999-02-26  0:00         ` Don Harrison
1999-02-26  0:00           ` fraser
1999-03-01  0:00             ` Don Harrison
1999-03-01  0:00               ` Matthew Heaney
     [not found]           ` <7b6nqe$75m$1@remarq.com>
1999-02-26  0:00             ` fraser
1999-02-27  0:00               ` Nick Roberts
1999-02-26  0:00           ` Samuel Mize
1999-03-01  0:00             ` Don Harrison
1999-03-01  0:00               ` Matthew Heaney
1999-03-02  0:00               ` fraser
1999-03-03  0:00                 ` Don Harrison
1999-02-28  0:00           ` Matthew Heaney
1999-02-28  0:00         ` Matthew Heaney
1999-02-25  0:00       ` robert_dewar
1999-02-26  0:00         ` Don Harrison
1999-02-26  0:00           ` robert_dewar
1999-02-26  0:00             ` dennison
1999-02-26  0:00             ` bourguet
1999-02-26  0:00               ` Samuel T. Harris
1999-02-27  0:00                 ` Jean-Pierre Rosen
1999-02-27  0:00                 ` Simon Wright
1999-02-28  0:00               ` dewar
1999-03-01  0:00                 ` bourguet
1999-03-01  0:00             ` Don Harrison [this message]
1999-03-01  0:00               ` robert_dewar
1999-03-03  0:00                 ` Don Harrison
1999-03-03  0:00                   ` robert_dewar
1999-03-01  0:00             ` Stephen Leake
1999-02-27  0:00         ` Brian Rogoff
1999-03-01  0:00           ` robert_dewar
1999-02-28  0:00       ` Matthew Heaney
1999-03-01  0:00       ` Tom Moran
1999-03-02  0:00         ` Matthew Heaney
1999-03-02  0:00           ` Tom Moran
1999-03-02  0:00             ` Matthew Heaney
1999-03-02  0:00               ` Tom Moran
1999-03-02  0:00                 ` Matthew Heaney
1999-03-02  0:00                   ` nabbasi
1999-03-02  0:00                     ` Matthew Heaney
1999-03-03  0:00                   ` Don Harrison
1999-03-03  0:00                     ` Single Extension; Polymorphic Arrays Nick Roberts
1999-03-03  0:00                       ` Nick Roberts
1999-03-08  0:00                         ` Matthew Heaney
1999-03-08  0:00                           ` Nick Roberts
1999-03-08  0:00                           ` Tucker Taft
     [not found]                             ` <m3ogm40wav.fsf@mheaney.ni.net>
1999-03-08  0:00                               ` Tucker Taft
1999-03-08  0:00                                 ` dennison
1999-03-09  0:00                                 ` Nick Roberts
1999-03-08  0:00                               ` Nick Roberts
1999-03-03  0:00               ` Can't export object of private type Don Harrison
1999-03-03  0:00                 ` Don Harrison
1999-03-03  0:00                   ` Nick Roberts
1999-03-04  0:00                     ` Don Harrison
1999-03-04  0:00                       ` fraser
1999-03-09  0:00                         ` Don Harrison
1999-03-04  0:00                       ` Nick Roberts
1999-03-04  0:00                         ` robert_dewar
1999-03-05  0:00                           ` Nick Roberts
1999-03-05  0:00                         ` Robert A Duff
1999-03-05  0:00                           ` Abstract Subprograms of Untagged Types Nick Roberts
1999-03-05  0:00                             ` robert_dewar
1999-03-05  0:00                             ` Tucker Taft
1999-03-05  0:00                               ` Nick Roberts
1999-03-06  0:00                               ` robert_dewar
1999-03-04  0:00                       ` Can't export object of private type Nick Roberts
1999-03-08  0:00                         ` Matthew Heaney
1999-03-09  0:00                         ` Don Harrison
1999-03-09  0:00                           ` Matthew Heaney
1999-03-09  0:00                             ` Nick Roberts
1999-03-10  0:00                             ` Don Harrison
1999-03-10  0:00                               ` Matthew Heaney
1999-03-08  0:00                     ` Matthew Heaney
1999-03-08  0:00                       ` Nick Roberts
1999-03-08  0:00                 ` Matthew Heaney
1999-03-10  0:00                   ` Don Harrison
1999-03-10  0:00                     ` Matthew Heaney
1999-03-10  0:00                       ` dennison
1999-03-10  0:00                         ` Robert A Duff
1999-03-10  0:00                           ` robert_dewar
1999-03-10  0:00                           ` dennison
1999-03-11  0:00                             ` dennison
1999-03-10  0:00                         ` robert_dewar
1999-03-10  0:00                           ` dennison
1999-03-10  0:00                             ` robert_dewar
1999-03-10  0:00                               ` dennison
1999-03-11  0:00                                 ` robert_dewar
1999-03-11  0:00                                   ` Don Harrison
1999-03-12  0:00                                     ` robert_dewar
1999-03-11  0:00                                 ` dennison
1999-03-11  0:00                                 ` bill
1999-03-11  0:00                                   ` dennison
1999-03-11  0:00                                   ` Scott Ingram
1999-03-11  0:00                                     ` Larry Kilgallen
1999-03-12  0:00                                   ` dewar
1999-03-11  0:00                           ` Don Harrison
1999-03-03  0:00           ` Don Harrison
1999-02-28  0:00     ` Matthew Heaney
1999-02-28  0:00   ` Matthew Heaney
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