Lenguaje Ada

Ada Distilled

by Richard Riehle

An Introduction to Ada Programming for Experienced Computer Programmers

by Richard Riehle

AdaWorks Software Engineering
http://www.adaworks.com
Copyright 2002, AdaWorks Software Engineering Public Edition. Permission to copy if AdaWorks is acknowledged in copies Version: July 2003

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Ada Distilled

by Richard RiehleAcknowledgments
There are always a lot of people involved in the creation of any book, even one as small and modest as this one. Those who have contributed to the best features of this book include my students at Naval Postgraduate School, Mr. Michael Berenato of Computer Sciences Corporation, Mr. Ed Colbert of Absolute Software, and many students from Lockheed-Martin Corporation, Computer SciencesCorporation, British Aerospace, various branches of the uniformed services, to name a few. I also owe a special thanks to Dr. Ben Brosgol, Dr. Robert Dewar, Mr. Mark Gerhardt, and Dr. Mantak Shing for what I have learned from them. Also thanks to the contributors to comp.lang.ada Usenet forum and the Team_Ada Listserve. Phil Thornley deserves extra credit for his detailed reading of the manuscript and manycorrections. Special thanks goes to Ed Colbert for his careful study of some of my program examples. He is one of those people who can spot a program error at fifty paces. Using this unique skill, Ed brought many errors, some big and some small, to my attention. Also thanks to more recent input from Phil Thornley and Adrian Hoe. Any other errors are strictly mine. mine and mine alone. Anymistakes in wording, spelling, or facts are

I hope this book will be valuable to the intended audience. It is moderate in its intent: help the beginning Ada programmer get a good start with some useful examples of working code. More advanced books are listed in the bibliography. The serious student should also have one of those books at hand when starting in on a real project.

Richard RiehleIntended Audience for this Book
This book is aimed at experienced programmers who want to learn Ada at the programming level. It is not a "...for dummies" book, nor is it intended as a program design book. Instead, we highlight some key features of the Ada language, with coded examples, that are essential for getting started as an Ada programmer. Ada is a rich and flexibile language used fordesigning large-scale software systems. This book emphasizes syntax, control structures, subprogram rules, and how-to coding issues rather than design issues. There are other really fine books available that deal with design. Also, this is not a comprehensive treatment of the Ada language. The bibliography lists some books that can help you once you have finished the material in this book. Think of thisa quick-start book, one that enables you, the experienced programmer, to get into the Ada language quickly and easily. The examples use text-oriented programs for simplicity of learning. If you prefer to do the exercises for a GUI environment, check out the sites listed for compilers and tools so you can download bindings for programming in a variety of windowing environments, including Wintel,Linux, and Unix. Of particular interest to those wanting to explore Window style programming are GtkAda, CLAW, GWindows, and JEWL. The last of these, JEWL, is especially useful if you have no prior experience writing Windows programs. Happy Coding,

Richard Riehle

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Ada Distilled

by Richard Riehle

Table of Contents
TABLE OF CONTENTS............................................................................................................................. 3 1. WHAT IS ADA DISTILLED? ................................................................................................................ 4 2. SUMMARY OF LANGUAGE ................................................................................................................ 5 3. TYPES AND THE TYPE MODEL...