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Ada FAQ: comp.lang.ada (part 2 of 3)

comp.lang.ada Frequently Asked Questions (and answers), part 2 of 3. Please read before posting. Does *not* get into Ada programming questions [for that see the companion Ada/programming FAQ].
Archive-name: computer-lang/Ada/comp-lang-ada/part2
Comp-lang-ada-archive-name: comp-lang-ada/part2
Posting-Frequency: monthly
Last-modified: 24 May 1996
Last-posted: 22 April 1996

                       Frequently Asked Questions (FAQ)

    Recent changes to this FAQ are listed in the first section after the table
    of contents. This document is under explicit copyright.

This is part 2 of a 3-part posting; part 1 contains the table of contents.
Part 3 begins with question 7; it should be the next posting in this thread.
Part 1 should be the previous posting in this thread.

4: Compilers

4.1: Is there a list of validated Ada compilers?

   Yes, indeed, there is. The latest list can be retrieved by anonymous
   FTP. For Ada 83, it is in
   (if the list is updated during the month, the previous one is

   And there is also a (non-empty!) list of validated Ada 95 compilers at

4.2: Is there a free Ada compiler (or interpreter)?

   There ARE indeed free Ada systems, and there is even choice: Ada/Ed
   for Ada 83, and AVLAda9X and GNAT for Ada 95. A complete list is
   available at

   (Strictly speaking these are free to distribute but NOT
   "public-domain". They are "free"--under copyright conditions known as
   "GNU Copyleft". In short: there is no warranty, and you are allowed to
   copy, modify, and distribute them; but you can't charge anyone for the
   software itself, and if the software (necessarily including source
   code) is further distributed, it must be done under the same
   conditions--i.e. copyable, with sources and modifications, available
   to everyone else, etc.)

    4.2.1: GNAT, The GNU NYU Ada Translator -- An Ada 95 Compiler

   GNAT is a compiler for Ada 95 that accepts Ada 95 source code and
   generates executable (machine) code (GNAT is a compiler and does not,
   repeat: DOES NOT, generate C code). It is based on the Free Software
   Foundation (FSF)'s gcc, a portable compilation system for a variety of
   languages. GNAT generates relatively good code, and is expected to
   improve further as its developers transition from developing initial
   functionality to optimizing it. GNAT supports tasking for many
   computer platforms, but it does NOT support tasking on MS-DOS at this
   time. For tasking with GNAT and a PC platform, consider using other
   operating systems such as Linux or OS/2 (while we're at it, if you use
   DOS, consider using a real operating system :-).

   GNAT is available from the New York University host, in directory There are versions for UNIX-based systems
   (Sun, DEC, IBM, Next, ...), and versions for DOS, OS/2, and NT 386/486
   systems. Usually the latest version is made available for both Sun
   SPARC (SunOS 4.1) and OS/2 systems.

   It is also available in the Public Ada Library (PAL -- formerly the
   Ada Software Repository), under directory (Internet
   address: A mirror site of the PAL also carries GNAT,

   You can also get a copy from the AdaIC Bulletin Board. But this is a
   dial-up operation (703/614-0215), and since the files sizes are large,
   connect times may be lengthy. The bulletin board is best used as a
   back-up source for those who don't have Internet/FTP access.


   (excerpted from "Free Source Code for GNAT 9X Compiler to be Available
   on Internet", by Robert Dewar and Edmond Schonberg, New York
   University, Ada Information Clearinghouse Newsletter August 1993)

   The Computer Science Department of the Courant Institute of
   Mathematical Sciences at New York University received a contract from
   the Ada 9X Project Office, under the direction of Christine M.
   Anderson, to develop a GNU/Ada system. The work was co-sponsored by
   ARPA and the Ada Joint Program Office.

   The final delivery was a full Ada 95 implementation with as much of
   the core language and annexes implemented as possible.

   Here is the official GNAT e-mail address:
          This address is to be used specifically to report problems with
          the currently available version of the GNAT system. Please be
          as specific as possible in reporting problems.

      OS/2 Version

   The executables and sources for the OS/2 version of GNAT are split and
   compressed into two files, each of which can fit on one 3.5-inch
   high-density diskette. Although it is possible to install GNAT on an
   OS/2 machine on FAT (MS-DOS-compatble) partition, such an installation
   will not be fully functional. In fact, GNAT does not support
   installations on FAT partitions. You will need about 8.5 MB of free
   disk space after you have copied the appropriate files to your hard
   drive. About half of this amount is taken up by the source code.

   In case you want to modify and re-compile GNAT, you will need about 24
   MB of free disk space after you have installed GNAT for OS/2 and
   copied the necessary source files to your hard drive.


   Several ports of GNAT have been produced by volunteers for a number of
   additional platforms (e.g. SPARCStations Solaris 2.1, i386/i486 Linux,
   DECstation (MIPS chip) Ultrix, DOS, SCO Unix). Users should allow time
   for the volunteers to catch up with the new releases.

   Note: The DOS version requires installation of DJGPP, DJ Delorie's
   port of GCC, GNU loader (ld), and GNU assembler (as) to DOS. DJGPP
   also includes the GO32 memory extender, which works with both VCPI and
   DPMI standards, which allows working in a Microsoft Window. There is
   information on DJGPP stored together with GNAT.

    4.2.2: Ada/Ed -- An Interpreter for Ada 83

   Ada/Ed is available for PCs, Unix-based machines, Amiga, and Atari
   systems. The Ada/Ed interpreter for Ada 83 is available from the New
   York University host, in directory
   (Internet address There you will find a version for
   UNIX-based machines, and a version for 386/486 DOS machines.

   Ada/Ed is a translator-interpreter for Ada. It is intended as a
   teaching tool, and does not have the capacity, performance, or
   robustness of commercial Ada compilers. Ada/Ed was developed at New
   York University, as part of a long-range project in language
   definition and software prototyping. The project produced the first
   validated translator for Ada, in the form of an executable definition
   of the language written in SETL. The SETL system served as design
   document and prototype for the C version.

   Ada/Ed was last validated under version 1.7 of the ACVC tests.
   Therefore it is not currently a validated Ada system, and users can
   expect to find small discrepancies between Ada/Ed and currently
   validated compilers.

   Apart from the 100-odd tests of ACVC 1.11 that Ada/Ed currently fails,
   the major deficiency of the system is that, being an interpreter, it
   does not implement most representation clauses, and thus does not
   support systems programming close to the machine level.

    4.2.3: GW-Ada/Ed -- a souped-up version of Ada/Ed for 386/486 DOS and
    Macintosh machines

   GW-Ada/Ed is available from the PAL, by anonymous FTP. The files are
   located in subdirectories "dos" and "mac" of directory

   This project was sponsored by The George Washington University, and in
   part by the United States Advanced Research Projects Agency (ARPA).

   This distribution contains the executables for GWAda, which consists
   of the NYU Ada/Ed translator/interpreter system together with an
   integrated editor developed by Prof. Arthur Vargas Lopes of the
   Pontifical University at Porto Alegre, Brazil. Lopes began his work on
   GWAda while he was a doctoral student at The George Washington
   University. There is also in the DOS version a very nice extended
   runtime facility, with interesting kinds of source tracing.

   GWAda is being freely distributed at no charge. In the near future the
   developers will make the source code available under the GNU General
   Public License. Source code is not being provided because the system
   is still in the developmental stage. Source code for Ada/Ed itself is
   available from NYU (see above) and from PAL (see questions 9.1 and

   Note that under DOS you do not have to use the GWAda integrated
   environment, but can execute the various parts of NYU Ada/Ed from the
   DOS command line, as described in the NYU instructions.

   System requirements:
     * IBM PC Compatible, 386 or 486, running MS-DOS or PC-DOS, with at
       least 3.6 MB available extended memory, and at least 5 MB free
       hard-disk space.

     * any Mac, System 7, with at least 2.5 MB of RAM, and around 10 MB
       free hard-disk space. Note that the new version is PowerPC native
       and blindingly fast (8-20 times faster than the 1.1 release).

4.3: What cheap (<500$) Ada compilers are available?

   What follows is absolutely *not* exhaustive, but inexpensive
   compilers are available, and some vendors offer educational discounts
   or free programs for educational sites. Among those offering
   educational discounts are DDC-I, Encore, Harris, IBM, Irvine Compiler,
   OC Systems, Rational, R.R., Tartan, and Thomson Software Products

   OC Systems: OC Systems will distribute PowerAda free to educational
   institutions wishing to use the product for teaching purposes. Contact
   by email

   Rational: Rational provides free software (Rational Apex) to
   accredited educational institutions, including military academies, in
   the United States and Canada. This is under its Software Engineering
   for Educational Development (SEED) program. To receive information on
   the program, send your contact information via e-mail to

   Rational also offers OpenAda for $99. (Rational Software Corporation,
   2800 San Tomas Expressway, Santa Clara, CA 95051-0951; tel:

   R.R. Software: R.R.'s Janus/Ada Professional Development System --
   80386 MS-DOS -- regularly goes for $500. (R.R. Software, P.O. Box
   1512, Madison, WI 53701; contact: Randall Brukardt 608/251-3133;

   Thomson Software Products (US pricing only): FirstAda for 286 DOS is
   $595. It will run on 286 and higher, and will generate applications
   for any x86 PC. Comes with a full toolset. Thomson Software Products
   does run specials on it periodically. Call Pat Michalowski at
   619/457-2700 for more info.

   Thomson Software Products offers the same compilation system for $144
   to qualified educational institutions under its LEAP program. The
   program also offers substantial educational discounts on other Thomson
   Software Products products, as well as site license arrangements.
   Contact Kathy Ruggiero at 617/270-0030 for more info.

4.4: Is there an Ada compiler for common machine X/common operating system Y?

   There are hundreds of Ada compilers available on the market. Some
   answers for Frequently Asked Compilers are listed below. If your
   specific question is not answered here, check the comprehensive list
   of validated Ada compilers (see 4.1).

    4.4.1: For the Macintosh

   It depends on whether you want a compiler for serious development or
   just a learning tool. The free GW-Ada/Ed-Mac (see question 4.2.3) is
   the latter; it works on all Mac architectures. GW-Ada is a nice
   learning tool with an easy-to-use IDE, but it generates interpreted
   virtual code, not Mac apps.

   Other than that there is the Rational (ex-Meridian) OpenAda. OpenAda
   is an Ada 83 compiler with a Toolbox binding and MPW 3.2, but Rational
   has dropped it and is not going to upgrade it to Ada 95. It has one
   limitation for large programs: Packages which contain more than 32K
   bytes of data will compile, but not link. It works with System 7, and
   has been reported both as working and not-working on PowerPCs (maybe
   due to a problem with Inits). It can be ordered from D.C. Heath (price
   Mac version 12 disks plus documentation (35630-1) PC versions Five 3
   1/2" disks plus documentation (35629-8) Nine 5 1/4" disks plus
   documentation (34139-8)

   A GNAT for Macintosh is in the works.

    4.4.2: Native compilers for OS/2

   There are several good fully validated compilers. E.g. Thomson
   Software Products (ex-Alsys) has one, and has a partial Ada 95
   compiler for Windows; RR Software specializes in the Intel x86
   architecture (AETECH repackages and distributes their compilers as
   IntegrAda) -- and they advertise a partial Ada 95 compiler. GNAT is
   available for OS/2.

4.5: How can I contact Ada compiler vendors?

   Here is a non-exhaustive list (possibly out-of-date, for the moment)
   of email and phone contacts for questions and/or sales.

Active Engineering Technologies, Inc.
    Tel: (619) 414-9001
    Fax: (619) 414-9192

Ada Core Technologies (ACT)
    Tel: (212) 620-7300
    Fax: (212) 807-0162

AETECH, Inc.: see Active Engineering Technologies

Alsys: see Thomson Software Products

  questions (Brian Allison)
    Tel: (214) 497-4346

  questions (Dave Thersleff)
    Tel: (612) 683-5701
  sales (Sylvia Crain)
    Tel: (505) 988-2468


    Tel: (602) 275-7172
    Tel: +45 45 87 11 44

Green Hills Software Inc.
  sales (Eric Schacherer)
    Tel: (805) 965-6044

Harris Computer Systems Corporation
  questions (Jeff Hollensen)

IBM: see OC Systems Inc.

  questions (Mike Ryer)

Irvine Compiler Corp (ICC)

Meridian: see Rational Software Corporation

OC Systems Inc.
    Tel: (703) 359-8160
    Fax: (703) 359-8161

Rational Software Corporation
    Tel: (408) 496-3600 or (800) RAT-1212

R.R. Software
    Tel: (800) Pc-Ada-4u or (800) 722-3248 (Randy Brukardt)

    Tel: (412) 856-3600 (ext 150)
    Tel: (800) 856-5255 or (412) 856-3600

TeleSoft: see Thomson Software Products

Thomson Software Products (ex-Alsys)
    Tel: (619) 457-2700
         (800) 833-0042 (ActivAda only)

Verdix: see Rational Software Corporation

   Note: The AdaIC's Validated Compiler List (see 4.1) now contains
   addresses, usually including e-mail, for compiler-vendor points of

4.6: Are Ada 95 compilers compatible with Ada 83?

   Yes, absolutely. Ada 95 is very close to upwards compatible with Ada
   83, so you will find that an Ada 95 compiler is in practice
   "compatible" with the Ada 83 compiler you have used or are using. The
   compatibility really depends on what kind of code you have written, so
   one should understand what has evolved, what was considered broken and
   is now fixed, as well as what is new. There are two excellent
   documents that will help immensely in that respect:
     * Changes to Ada -- 1987 to 1995, in a Postscript 362KB file:
       also available in a text-only 207KB file:

     * Ada 9X Compatibility Guide, by Bill Taylor, in directory

   Furthermore, GNAT has a -gnat83 switch which enforces most of the Ada
   83 restrictions, and other compilers have similar 95/83 modes.


5: Organizations that deal with Ada and Ada issues

5.1: Ada Joint Program Office (AJPO)

   The AJPO is part of the U.S. Department of Defense; it was created to
   facilitate the implementation of the DoD's Software Initiative (Ada)
   throughout the Services, and maintain the integrity of the Ada
   language. The AJPO sponsors the AdaIC (see below).

   NOTE: The AJPO is scheduled to shut down in 1997. Its functions will
   probably be transferred to other entities.

   The address is:

5600 Columbia Pike
Falls-church, VA 22041

phone: (703) 681-2459

   The current staff are:

          Dr. Charles B. ("Chuck") Engle, Jr. --

   Acting AJPO Program Manager
          Ms. Joan McGarity --

   Contracts Liaison
          Mr. Gary Shupe --

5.2: Ada Information Clearinghouse (AdaIC)

   The Ada Information Clearinghouse (AdaIC) provides a full spectrum of
   information on Ada to anyone interested in finding out more about the
   programming language. IIT Research Institute operates the AdaIC for
   the Ada Joint Program Office (AJPO).

   Their address is:

Ada Information Clearinghouse
P.O. Box 1866
Falls Church, VA 22041

phone: (703) 681-2466
fax:   (703) 681-2869
(800) Adaic 11 (232-4211)


   The AdaIC publishes a quarterly newsletter, which contains current
   news, Ada conference reports, announcements from the AJPO Director,
   and articles on projects using Ada. If you would like to receive a
   copy of the AdaIC newsletter, call and request a subscription. There
   is no charge. The AdaIC also regularly updates and publishes more than
   70 separate information flyers. Flyer topics include:
     * Ada Validated Compilers
     * Ada News and Current Events
     * Ada Usage
     * Ada 9X Project
     * On-line sources of Ada Information
     * Ada Bibliographies
     * Ada Compiler Validation and Evaluation
     * Resources for Ada Education and Training
     * Ada Software, Tools, and Interfaces
     * Ada Regulations, Policies, and Mandates
     * Ada Historical Information

   One of the most commonly requested flyers is the Validated Compilers
   List. This list, which is updated monthly, contains Ada compilers that
   have been validated by the AJPO. For the most current information on
   validated Ada compilers, contact the AdaIC.

   Practically all AdaIC flyers are available via anonymous FTP from
   their host, in directory

5.3: Association for Computing Machinery's Special Interest Group on Ada (ACM

   SIGAda's bimonthly publication is Ada Letters.

   Price for non-members: $55 (Annual ACM membership dues, $82; students,

   Otherwise it costs $20 per year to ACM members; $10 per year to ACM
   student members.

   The address is:

Association for Computing Machinery, Inc.
1515 Broadway
New York, NY 10036

   SIGAda also has a number of committees and working groups on a variety
   of topics.

5.4: ISO Working Group 9 (ISO-IEC/JTC1/SC22/WG9, WG9 for short)

   This is a working group that deals with Ada within the International
   Standardization Organization. For more information, you can find
   online information about WG9 at

   There are several Rapporteur (rap) groups with WG9:
     * ARG: Ada Rapporteur Group -- Comments and Interpretations
     * CRG: Character Rapporteur Group -- International Character Sets
     * IRG: Information Systems Rapporteur Group -- Decimal Arithmetic
     * NRG: Numerics Rapporteur Group -- NUMWG packages
     * RRG: Real-Time Rapporteur Group -- ExTRA
     * SRG: SQL Interfaces Rapporteur Group -- SAMeDL
     * URG: Uniformity Rapporteur Group -- Portability through Uniformity
     * XRG: Ada 9X Rapporteur Group

   Ada Rapporteur Group (ARG):
          This is the group responsible for evaluating comments on the
          Ada standard. Officially, the group is only developing a
          technical report addressing comments and questions concerning
          the ISO standard for Ada. (Arcane ISO rules prevent the ARG or
          WG9 from issuing "official" interpretations of a standard.) In
          practice, when a response to a comment is approved by WG9, the
          response is taken into account by the Ada Validation Office and
          affects the test suite. The documents containing comments on
          the standard and ARG responses are called "Ada Commentaries"
          and are given numbers of the form AI-ddddd/vv, where vv is a
          version number.

          Comments and questions about the Ada standard should be sent to
, using the format
          specified in the Ada standard. You can receive e-mail
          notification of an update to a commentary (optionally including
          the text of the commentary) by sending a request to
 Commentaries are
          generally updated only a few times each year. The text of all
          commentaries is available by anonymous FTP from the AdaIC site
          in the account public/ada-comment. A detailed discussion of ARG
          procedures and the format of commentaries can be found in the
          ada-comment account in the file arg-procedures.doc. A
          reformatted copy of the Reference Manual that includes
          WG9-approved commentaries used to be available from Karl Nyberg
          (, but note that distribution of the Ada 83
          AARM has been transferred by Grebyn Corporation to the Ada
          Resource Association (3.1.1).

   Uniformity Rapporteur Group (URG)
          Responsible for evaluating Uniformity Issues (UIs). UIs
          specify/recommend specific choices for the compiler
          implementor, where the language permits implementation freedom.
          The "canonical example" is UI-8, on integer types. This UI
          recommends that integers be at least 32 bits, and provides
          names for the other predefined integer types. The goal of the
          URG and the UI's is to further Ada portability by providing
          uniform implementations of implementation-dependent features
          commonly used by Ada applications.


6: Tools

6.1: Is there an Ada-mode for Emacs?

   There are 3 Ada modes for Emacs:
     * the most recent and powerful one is available by FTP in the file
       emacs-ada-mode-2.12.tar.gz in directory

       This is still work under development but it is already quite
       usable. The main features are:
          + compile and parse the errors (with the cursor at the right
            line AND column)
          + highlight keywords and comments
          + create skeletons for all Ada constructs (both 83 and 9x)
          + goto next (previous) subprogram/package/task
          + goto beginning of syntactic construct
          + name completion (works across file boundaries, if the Xref
            output from gnatf is available)
          + TAB ---> indent (almost always correctly)
          + untabify, remove trailing spaces automatically before saving
          + C-c C-f ---> format subprogram specs in GNAT style
          + and much more to come...
   The 2 main developers are Markus Heritsch (who works under the
       direction of Franco Gasperoni at ENST, Paris) and Rolf Ebert
       (Munich, Germany).

     * electric-ada, by Steven D. Litvintchouk of Mitre Corp (available
       from?--NO INFORMATION); and

     * gnu-ada mode. Here is a small description of the features of this

        Compile programs within emacs
                Run compiler as inferior of Emacs, and parse its error
                messages. NOTE: I believe that this feature will only
                work with VADS, but it might have been tailored to work
                with other compilers.

        Ada dired
                It supplies a form of dired that helps manage the VADS
                environment, and it adds ADA vads commands into ada mode.
                Unlike a previous dired-ada implementation, this version
                uses the existing dired mode functions except where there
                is unresolvable conflict. Thus, this is more like a minor
                mode to dired. Very important because on actual version
                of emacs 19(beta), in fact lemacs (lucid emacs), dired
                has changed and we can no longer use gnu-ada mode :-(

        you can consult the Ada Language Reference Manual (*) during
                parsing error message.
                (*)You can get one in e.g. the Public Ada Library.

        smart indentation
                Tries hard to do all the indenting automatically.
                Emphasizes correct insertion of new code using smart

        Smart template commands (bnf)
                This is essentially a bnf processor/language-sensitive
                editor. The next message will give you an ada bnf file
                that you can use within ada-mode to expand nonterminals.
                But you can roll your own grammars (e.g., your design
                grammar or an ADL) and put them in *.bnf files ... The
                BNF rule set is stored as a list of rules.

        debugging Ada programs within emacs
                A facility is provided for the simultaneous display of
                the source code in one window, while using a.db to step
                through a function in the other. A small arrow "=>" in
                the source window, indicates the current line.

        Move from procedure to procedure or package to package

        tags Ada

        and other things ...

   You can find the gnu-ada mode in where did it go? as well as in the
   PAL, under directory

6.2: Are there versions of lex and yacc that generate Ada code?

   The Arcadia project produced the tools aflex and ayacc, both written
   in Ada and producing Ada code. They can be found in directory (Internet address:,

6.3: Where can I get a yacc/ayacc grammar to read Ada code?

   A yacc and lex grammar for Ada 83 is available via FTP from the
   comp.compiler archives at and via e-mail from the
   compilers server at .

   A yacc grammar for Ada 95 is available in file

   and a lex grammar for Ada 95 is available in file

6.4: What is Anna, and where can I get it?

   Anna is a language for formally specifying Ada programs. It extends
   Ada with various different kinds of specification constructs from ones
   as simple as assertions, to as complex as algebraic specifications. A
   whole lot of tools have been implemented for Anna, including:
    1. The standard DIANA extension packages, parsers, pretty-printers.
    2. Semantic checker (very similar to standard semantic checkers for
       programming languages).
    3. Specification analyzer -- this is a tool used to test a
       specification for correctness before a program based on the
       specification is written.
    4. Annotation transformer -- this transforms Anna specification
       constructs into checks on the Ada program that is developed based
       on the specification. This tool is currently in the process of
       being enhanced so that it can handle at least all the legal Ada
       programs in the ACVC test-suite.
    5. Runtime debugger -- The instrumented program output by the
       annotation transormer can be run with a special debugger that
       allows program debugging based on formal specifications.

   All tools have been developed in Ada and are therefore extremely
   portable. Anna has been ported to many platforms, details of which can
   be obtained from the person who handles Anna releases. You can send
   e-mail to for answers to such
   questions. Actually, there is also a mailing list -- Send e-mail to the earlier address if
   you want to get on this list.

   One could view Anna and its toolset as a *very* significant
   enhancement of assertions that are provided in languages such as C
   (using the assert statement). The enhancements are in the form of both
   (1) many more high level specification constructs; and (2) more
   sophisticated tool support.

   However, there are those who would not even wish to compare Anna with
   C assertions! :-)

   The Anna tools may be found in directory

6.5: What is DRAGOON, and where can I get it?

   DRAGOON is a language, implemented as an Ada preprocessor (i.e., it
   generates pure Ada). DRAGOON is truly object-oriented, including
   complete support for multiple inheritance. A very nice feature of
   DRAGOON not found in many OO languages is the concept of "behavioral"
   inheritance. This allows you to keep the concurrent behavior of object
   separated from the object class hierarchy.

   The book by Colin Atkinson, "Object-Oriented Reuse, Concurrency and
   Distribution: An Ada-Based Approach" (ACM Press, 1991, ISBN:
   0201565277), is very well written and describes the language
   succinctly and completely.

   For a copy of the preprocessor, contact:

Mr. Andrea Di Maio
TXT Ingegneria Informatica S.p.A.
Via Socrate, 41
20128 Milan, ITALY
phone: + 39-2-2700 1001

6.6: Where can I get language translators?

   The AdaIC maintains a Products and Tools Database on its bulletin
   board (703/614-0215), and one of the categories is translators. (The
   list of products should not be considered exhaustive; if you wish to
   suggest additions, please contact the AdaIC.) Besides access to the
   database via the bulletin board, you can also call the AdaIC
   (800-AdaIC-11 or 703/685-1477) and ask for a customized search.

    Should I?

   In addition to all the usual caveats, however, it should also be noted
   that translation itself is a controversial issue.

   When a project makes the transition to Ada from some other language,
   one question that arises is whether to translate older code into Ada.
   Among the immediate considerations are how much of the code can in
   fact be translated by a program intended for that purpose, versus how
   much will still require re-coding by hand. And will the translated
   code suffer a significant loss in speed of execution? Further, a
   project must consider whether the translated code will reflect sound
   software engineering and be readily understandable and modifiable. Or
   will the translated code be merely "Fortranized Ada" or "Cobolized
   Ada", or the like, possibly retaining limitations present in the
   earlier code? Portability is also a problem.

   The resolution of such issues will require an understanding of the
   earlier code, an appreciation of the similarities and differences
   between its language and Ada, and an evaluation of the translation
   program under consideration.

6.7: What is ASIS?

   The Ada Semantic Interface Specification is a layered
   vendor-independent open architecture. ASIS queries and services
   provide a consistent interface to information within the Ada Ada
   compilation environment. Thus it is envisioned that tool makers should
   be able to create ASIS clients--shielded and free from the
   implementation details of each Ada compiler vendor's proprietary
   compilation environment and intermediate representation(s).

   ASIS Version 1.1.1 is the last version of the ASIS83 (Ada═83) de facto
   industry standard; it was finalized, together with the corresponding
   test suite for ASIS implementations, in June 1994.

   The current version of ASIS 95 is ASIS 2.0.E (November 1995). As
   errors, misunderstandings, and clarifications are discovered, the ASIS
   Working Group will release new edited versions of the specification.

   For more information, there is an ASIS WWW server at

   ASIS versions are available in directory

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