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!standard N(0)          19-04-05 AI12-0330-1/00
!class Amendment 15-06-03
!status work item 15-06-03
!status received 15-03-20
!priority Low
!difficulty Easy
!subject Add items to the Glossary
!summary
** TBD.
!problem
We've defined a number of new concepts in Ada 2020, among them "parallel constructs", "logical thread of control", "reduction", "default initial condition", and "stable property". At least some of these should be added to the Glossary.
!proposal
(See Summary.)
!wording
** TBD.
!discussion
!ASIS
[Not sure. It seems like some new capabilities might be needed, but I didn't check - Editor.]
!ACATS test
ACATS B- and C-Tests are needed to check that the new capabilities are supported.
!appendix

From: Randy Brukardt
Sent: Friday, March 8, 2019  7:39 PM

>Annex N I would like more items, such as Attribute, Check, Master, 
>Operational Aspect, Representation Aspect, Subunit, Suppress.  But I 
>think I had Annex N to review for Ada 2012 too and my request was 
>turned down then.

Some of those terms might be valuable, but I'd guess it would be even more 
useful to add some terms around parallel constructs, like say, "parallel 
construct" :-), "logical thread of control", and "reduction".

Do we have someone volunteering to propose some additional Glossary entries 
(including the definitions, silly :-)??

P.S. I believe that Jeff is away on "holiday", so we can't talk him into it 
today.

***************************************************************

From: Jeff Cousins
Sent: Thursday, April 4, 2019  8:49 PM

> You're right, of course, but we need Glossary entries for lots of things 
and I didn't get any volunteers when I asked last month.
 
Hereís a shot at the items that I suggested.  No doubt as everyone knows a 
bit about this everyone will comment.
 
Attribute
A characteristic or property of an entity that can be queried, and in some 
cases specified.  (I darenít tackle how this overlaps with aspect!).

Check
A test made during execution that some unusual condition has not occurred.

Master
The execution of a construct that includes the finalisation of local objects 
(after completion but before leaving).

Operational Aspect
Aspects other than Representation Aspects.

Representation Aspect
An aspect that affects how an entity is mapped onto the underlying hardware, 
for example the size or alignment of an object.

Subunit
A body that can be compiled separately from its embracing library unit. (Only 
GNAT doesnít ? ).

Suppress
To turn off a run-time check.

***************************************************************

From: Randy Brukardt
Sent: Thursday, April 4, 2019  8:49 PM

Great, but that doesn't include anything NEW, which seems to be the most 
critical need.

Ed asked for "default initial condition", presumably because all of the other 
assertion contracts already have a glossary entry (and that was obvious in the 
text he was reviewing 

I had suggested at a minimum "parallel construct", "logical thread of 
control", and "reduction". There may be others.

P.S. I need to know where to place the entries as well. Glossary entries are 
actually given in as AARM notes next to the formal definition (scattered about 
the Standard); the tools make the actual annex at the end. Side thought: it's 
a bit annoying that the information about the location of the formal definition 
isn't displayed in the glossary, since that wouldn't be very hard to do, at 
least in non-ISO editions.

***************************************************************

From: Randy Brukardt
Sent: Friday, April 5, 2019  11:02 PM

...
>Hereís a shot at the items that I suggested.  No doubt as everyone 
>knows a bit about this everyone will comment.

So far this message has gotten the same response as the original call for a 
volunteer. I suppose that says something too.
	 
...
>Master
>
>The execution of a construct that includes the finalisation of local 
>objects (after completion but before leaving).

We just had a long discussion of 's' vs. 'z' in "finalization". Hope we don't 
have another one. :-)

>Operational Aspect
>Aspects other than Representation Aspects.

Not strictly true, there are a few that aren't officially classed as either. 
If they have enough rules (like "Pre"), that doesn't matter. In any event, 
this is rather circular. It should say something about properties, as in 
13.1. Maybe:

An aspect that defines properties of an entity other than representation 
properties (see Representation Aspect).
	 
>Subunit
>A body that can be compiled separately from its embracing library unit.  
>(Only GNAT doesnít ? ).

I'm pretty sure we can't put emojies into the Standard; probably can't refer 
to GNAT either. ;-)

***************************************************************

From: Jeff Cousins
Sent: Saturday, April 6, 2019  3:49 AM

>>The execution of a construct that includes the finalisation of local objects 
>>(after completion but before leaving).

>We just had a long discussion of 's' vs. 'z' in "finalization". Hope we don't 
have another one. :-)
 
Iíd deliberately typed Ďzí in deference to my American colleagues, but the 
spell-checker must have auto-corrected it.

***************************************************************

From: Jeff Cousins
Sent: Saturday, April 6, 2019  12:04 PM

> Great, but that doesn't include anything NEW, which seems to be the 
> most critical need.
 
I actually see the newer terms as being less important as they're for the more 
advanced users, whereas some of the older terms are building blocks for how 
Ada views the world, and should have been in the glossary years ago.

I would prefer the authors of the relevant AIs to state their intended 
meaning rather than me potentially second-guessing them, but I've had a go at 
a few of them.

> Glossary entries are actually given in as AARM notes next to the formal 
> definition 
 
Iím hoping that the glossary terms are more user-friendly than the sometimes 
convoluted words of the formal definition.

Attribute

A characteristic or property of an entity that can be queried, and in some cases specified.
(First defined in 4.1.4).

 

Check
A test made during execution that some unusual condition has not occurred.
(These are mentioned all over the place, but the place to talk about them in general rather than specific checks looks to be 11 Exceptions).

 
Default Initial Condition
A condition that must hold true after the default initialization of an object. 
(Defined in 7.3.3 (2.a/5).

Logical Thread of Control
To paraphrase Wikipedia:
The smallest sequence of programmed instructions that can be scheduled independently.
(This is the successor to Task as the lowest level concurrent entity for most purposes, but Task wasn't defined in the Glossary either.
If we are going to define it, presumably it should go in 9 - 5.1 says see 9 for a definition, but there isn't (yet) a definition there).

Master
The execution of a construct that includes the finalization of local objects (after completion but before leaving).
(Defined in 7.6.1).

Operational Aspect
An aspect that defines properties of an entity other than representation properties (see Representation Aspect).
(Defined in 13.1).

Parallel Construct
A parallel construct is a construct that introduces additional logical threads of control without creating a new task. Parallel loops and parallel block statements are examples of parallel constructs.
(Defined in 5.1).

Reduction Expression
A reduction expression maps or transforms a collection of values into a new set of values, and then summarizes the values produced by applying an operation to reduce the set to a single value result.
(Defined in 4.5.10).

Representation Aspect
An aspect that affects how an entity is mapped onto the underlying hardware, for example the size or alignment of an object.
(Defined in 13.1).

Subunit
A body that can be compiled separately from its embracing library unit.
(Defined in 10.1.3).
 
Suppress
To turn off a run-time check.
(Defined in 10.5).

***************************************************************

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