HIGHLIGHTS of the June 1995 ASISWG/ASISRG Meeting
The Ada Semantic Interface Specification Working Group (ASISWG) and
the Ada Semantic Interface Specification Rapporteur Group (ASISRG)
met at the Washington Ada Symposium (WAdaS'95) in McLean, Virginia,
the United States from 26-27 June 1995. We made significant progress
towards developing an ASIS 95 specification for eventual ISO
standardization. Highlights from this meeting include:
- This represented the first joint meeting of ASISWG and the newly
formed ASISRG. On 28 April 1995, ISO/IEC SC22/WG9 unanimously
voted to pursue the standardization of ASIS. A new work item
will be submitted to SC22 for formal approval in September 1995.
At this June meeting, the roles of ASISWG and ASISRG were
discussed as was the wording for the ASISRG new work item.
ASISRG will standardize ASIS as a stand alone international
standard.
- Differences in the understanding of terminology had created
significant confusion and flames over the net. We spent a great
deal of time spent ironing out an understanding of the meaning
of words and phrases we use as a group in discussion. This went
a long way toward helping us broaden our scope. The agreement to
use RM95 terminology and not conflict with its definition was
important in removing some of the confusion we encountered when
discussing ASIS.
- The ASIS Library Model has become an ASIS Environment Model to
support the changes from Ada 87 to Ada 95. Ada 87 had notions of a
library, compilation/recompilation order, and obsolete units;
Ada 95 replaces these notions with an Ada environment, semantic
dependencies, and a consistent set of the unit supporters. ASIS
has been redefined as follows:
- The Ada Semantic Interface Specification (ASIS) is an
interface between an Ada environment as defined by ISO/IEC
8652 (the Ada 95 Reference Manual) and any tool requiring
information from this environment. An Ada environment
includes valuable semantic and syntactic information. ASIS
is an open and published callable interface which gives
CASE tool and application developers access to this
information. ASIS has been designed to be independent of
underlying Ada environment implementations, thus supporting
portability of software engineering tools while relieving
tool developers from having to understand the complexities
of an Ada environment's proprietary internal
representation.
Earlier ASIS definitions assumed the presence of persistent data
in a heavyweight Ada program library. The current definition has
no requirement to maintain persistent data and thus facilitates
many implementations with lightweight Ada environments.
- The heart of the meeting addressed the new version of the ASIS 95
Element_Kind Type Hierarchy and the proposed changes to ASIS87
to produce the ASIS 95 draft standard. Together, these will form
the basis for the ASIS 95 specification and standard. These
revisions reflect the new ASIS Environment Model. They were
approved as modified and will be maintained as:
- Issue 001 Proposed ASIS 95 Element_Kind Type Hierarchy
- Issue 002 Proposed change to ASIS87 to produce ASIS 95 draft standard
Still needed to produce the first draft standard are additional
clarifying commentary, conversion into an ISO format, and the
identification of additional queries, specially for the Ada 95 OO
model. We would appreciate input from OO experts so ASIS can
provide the appropriate level of interfaces.
- We are planning to distribute the first draft of ASIS 95 at Tri-
Ada'95 in November 1995.
- Although degrees of conformance cannot be addressed until the
ASIS 95 specification is better defined, preliminary conformance
issues were discussed. A minimum capability would support the
environment semantics providing an external (black box) view of
Ada compilation units. This implies full support of the packages
ASIS_Environment, ASIS_Libraries, and ASIS_Compilation_Units.
These packages are being modified to support the new concept of
the ASIS Environment Model and support of the minimum
conformance requirement. Other degrees of conformance may be
based on the ease of implementation, classes of semantic
information for views internal (white box) to the compilation
units, and support of data decomposition.
- ASISWG/ASISRG has been working very closely with Moscow State
University for their implementation of ASIS for the GNAT Ada 95
compiler. Their experience has been a valuable input for
evolving the ASIS specifications to support lightweight Ada 95
environments and for developing the ASIS Environment Model. The
initial version of their ASIS interface has been implemented.
Sample ASIS applications can now be built that can structurally
decompose Ada 95 compilation units down to the
statements/declarations level. An ASIS Workshop centered around
this tool is planned for Friday 6 October 1995 in conjunction
with the Ada in Europe 95 Conference. For details, please
contact either Sergey Rybin of Moscow State University
(rybin@alex.srcc.msu.su) or Alfred Strohmeier of the Swiss
Federal Institute of Technology (alfred.strohmeier@di.epfl.ch).
- There are two ASIS tutorials soon to be available in the public
domain. ASISWG/ASISRG thanks Rational and Thomson for their
valuable contribution to the Ada community. These will soon be
available on the asis host [sw-eng.falls-church.va.us host in
the /public/AdaIC/work-grp/asiswg directory]. Links on the WWW
=> http://www.acm.org/sigada/wg/asiswg provide access to all
information on the asis host.
I would like to thank all those who participated in making this
meeting a success including those attending in person and those
contributing by email. Detailed minutes of the meeting will be posted
to the asis host. The next meeting will be held in conjunction with
TRI-Ada'95 on 2-4 November 1995 in San Diego, California, in the
United States.
v/r
Currie Colket
Chairman, ASISWG/ASISRG
colket@smtp-gw.spawar.navy.mil or colket@sw-eng.falls-church.va.us
Phone: +1 (703) 602-1483 FAX: +1 (703) 602-6805
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Last update 11 August 1995. Questions, comments to
Clyde Roby (CRoby@IDA.Org)