USE OF MACHINE-READABLE Ada REFERENCE MANUAL The Ada Joint Program Office does not guarantee that accuracy of these files, as compared with the contents of ANSI/MIL-STD-1815A-1983, the Reference Manual for the Ada* Programming Language. If errors or discrepancies are found in this machine-readable version, please forward comments via the Defense Data Network (DDN) to Ada-Info@Ada20.ISI.EDU or via conventional mail to Ada Information Clearinghouse 3D139 (1211 S. Fern, C-107) The Pentagon Washington, D.C. 20301-3081. ----------------------------------------------------------------------- Copyright 1980, 1982, 1983 owned by the United States Government as represented by the Under Secretary of Defense, Research and Engineering. All rights reserved. Provided that notice of copyright is included on the first page, this document may be copied in its entirety without alteration or as altered by (1) adding text that is clearly marked as an insertion; (2) shading or highlighting existing text; (3) deleting examples. Permission to publish other excerpts should be obtained from the Ada Joint Program Office, OUSDRE (R&AT), The Pentagon, Washington, DC 20301-2081, U.S.A. Ada* is a registered trademark of the United States Government, Department of Defense, Under Secretary for Research and Engineering. Its use is administered by the Ada Joint Program Office (AJPO). In all contexts, use of the term "Ada" should indicate conformance to the standard. In keeping with policies on voluntary conformance, use of the term Ada is equivalent to a voluntary statement of conformance to the standard. The use of the trademarked term Ada will be made freely available to those who use it to indicate conformance to the standard and in accordance with the following guidelines: In any published material the first appearance of the term Ada must be properly acknowledged and include the statement "Ada is a registered trademark of the U.S. Government (Ada Joint Program Office)." Describing, advertising, or promoting a language processor as an "Ada" processor is equivalent to making a voluntary statement of conformance to ANSI/MIL-STD-1815A. The term Ada may be used in describing language processors which are not completely conforming or are not making a claim of conformance provided that there is a precise, easily visible statement of their non-conformance at the same time and in the same context. Uses of the term Ada other than those described above, including all organizations, companies and product names incorporating or utilizing the term Ada, need written authorization from the AJPO. Those persons advertising or otherwise promoting a language processor asserted as being a standard Ada processor for sale or public use are required to provide the AJPO with evidence sufficient to demonstrate conformance to the Ada standard. Use of the trademark does not imply any endorsement or warranty of the product by either U.S. DoD or ANSI. The Department of Defense (DoD), as the trademark owner, will allow others to use the Ada trademark free of charge and will not take action to prevent use of the Ada trademark so long as the trademark is used properly according to the above policy. Misuse of the trademark may lead to legal action. In the interest of information interchange, all users of this standard are encouraged to contact the Ada Joint Program Office, Department of Defense, OUSD(R&E), Washington, D.C. 20301, U.S.A. Users of the trademark and those reprinting the standard are required to notify the AJPO. *Ada is a registered trademark of the U.S. Government (Ada Joint Program Office). Foreword Ada is the result of a collective effort to design a common language for programming large scale and real-time systems. The common high order language program began in 1974. The requirements of the United States Department of Defense were formalized in a series of documents which were extensively reviewed by the Services, industrial organizations, universities, and foreign military departments. The Ada language was designed in accordance with the final (1978) form of these requirements, embodied in the Steelman specification. The Ada design team was led by Jean D. Ichbiah and has included Bernd Krieg-Brueckner, Brian A. Wichmann, Henry F. Ledgard, Jean-Claude Heliard, Jean-Loup Gailly, Jean-Raymond Abrial, John G.P. Barnes, Mike Woodger, Olivier Roubine, Paul N. Hilfinger, and Robert Firth. At various stages of the project, several people closely associated with the design team made major contributions. They include J.B. Goodenough, R.F. Brender, M.W. Davis, G. Ferran, K. Lester, L. MacLaren, E. Morel, I.R. Nassi, I.C. Pyle, S.A. Schuman, and S.C. Vestal. Two parallel efforts that were started in the second phase of this design had a deep influence on the language. One was the development of a formal definition using denotational semantics, with the participation of V. Donzeau-Gouge, G. Kahn, and B. Lang. The other was the design of a test translator with the participation of K. Ripken, P. Boullier, P. Cadiou, J. Holden, J.F. Hueras, R.G. Lange, and D.T. Cornhill. The entire effort benefitted from the dedicated assistance of Lyn Churchill and Marion Myers, and the effective technical support of B. Gravem, W.L. Heimerdinger, and P. Cleve. H.G. Schmitz served as program manager. Over the five years spent on this project, several intense week-long design reviews were conducted, with the participation of P. Belmont, B. Brosgol, P. Cohen, R. Dewar, A. Evans, G. Fisher, H. Harte, A.L. Hisgen, P. Knueven, M. Kronental, N. Lomuto, E. Ploedereder, G. Seegmueller, V. Stenning, D. Taffs, and also F. Belz, R. Converse, K. Correll, A.N. Habermann, J. Sammet, S. Squires, J. Teller, P. Wegner, and P.R. Wetherall. Several persons had a constructive influence with their comments, criticisms and suggestions. They include P. Brinch Hansen, G. Goos, C.A.R. Hoare, Mark Rain, W.A. Wulf, and also E. Boebert, P. Bonnard, H. Clausen, M. Cox, G. Dismukes, R. Eachus, T. Froggatt, H. Ganzinger, C. Hewitt, S. Kamin, R. Kotler, O. Lecarme, J.A.N. Lee, J.L. Mansion, F. Minel, T. Phinney, J. Roehrich, V. Schneider, A. Singer, D. Slosberg, I.C. Wand, the reviewers of Ada-Europe, AdaTech, Afcet, those of the LMSC review team, and those of the Ada Tokyo Study Group. These reviews and comments, the numerous evaluation reports received at the end of the first and second phase, the nine hundred language issue reports and test and evaluation reports received from fifteen different countries during the third phase of the project, the thousands of comments received during the Ansi Canvass, and the on-going work of the Ifip Working Group 2.4 on system implementation languages and that of the Purdue Europe LTPL-E committee, all had a substantial influence on the final definition of Ada. The Military Departments and Agencies have provided a broad base of support including funding, extensive reviews, and countless individual contributions by the members of the High Order Language Working Group and other interested personnel. In particular, William A. Whitaker provided leadership for the program during the formative stages. David A. Fisher was responsible for the successful development and refinement of the language requirement documents that led to the Steelman specification. This language definition was developed by Cii Honeywell Bull and later Alsys, and by Honeywell Systems and Research Center, under contract to the United States Department of Defense. William E. Carlson and later Larry E. Druffel served as the technical representatives of the United States Government and effectively coordinated the efforts of all participants in the Ada program.