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Full information on this text is available from the Addison-Wesley web page.
To put these sections in the context of their respective textbook chapters, see the Full Table of Contents. For further discussion of the overall philosophy of the book, see the Preface. All these HTML files are adapted from an HTML version of the textbook which is supplied on the Aonix ObjectAda CDROM.
This web site consists of sections of this textbook dealing with the Spider package, a simple "turtle graphics" package used for instructional purposes. Spider concepts are introduced throughout the book, to reinforce the fundamental problem solving and program design material: control structures and algorithms, data structures and abstract data types, math libraries and random numbers, concurrent programming, and so on.
Spider is an abstract data object (ADO) with a very simple interface (set of available operations or methods). A student with very little programming experience can start using it. Indeed, spider is introduced in Chapter 3 of the text, a book requiring no previous programming experience.
Furthermore, the implementation of Spider is straightforward and uncluttered, and discussed in detail in Chapter 7. Students who have reached this chapter--they have completed just over a half semester of programming--can understand this implementation. This is perhaps the most educationally important feature of Spider: It is a "fun" package whose use provides instant feedback and "live action," yet its inner workings are within reach of novices, so it is not "magic" to them.
The Spider package and all the associated programs are written in standard Ada 95, and can be compiled and executed on any computer or operating system platform supporting an Ada 95 compiler. The Spider package requires no special display hardware beyond an ANSI-compatible text terminal or emulator such as a VT100 or the ANSI.SYS of DOS computers. We are indebted to John Dalbey for the original Spider package from which this one has been adapted.
These programs have been tested with the GNAT (GNU Ada 95) system--available by anonymous ftp (from ftp://cs.nyu.edu/pub/gnat and many mirrors) for DOS, Windows 95/NT, Linux, OS/2, Power Macintosh, SunOS, Solaris, Irix, HP/UX, DEC/OSF and other systems--and also with the AcademicAda/ObjectAda family from Intermetrics and Thomson.
3.7 System Structures: Using a Screen Control Package
3.8 Continuing Saga: Introducing the Spider
7.3 Continuing Saga: Random Numbers and the Drunken Spider
7.7 Continuing Saga: Inside the Spider Package
Copyright ©1996 by Addison-Wesley Publishing Company, Inc.