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1 I7te Icon9{czsCcttcr No October 15,1990 Version 8 of Icon Version 8 of Icon is now stable and there are implementations available for all platforms previosly spported. We've sent ot a lot of copies of Version 8 over the last few months and we presme most persons sing Icon have pgraded to the new version. If yo're still sing an older version, yo shold seriosly consider moving to Version 8. It has new featres, it's faster, and there's complete, self-contained docmentation for Version 8 in the second edition of The Icon Programming Langage. The Icon Project also can no longer provide help with problems that may come p with earlier versions of Icon. For the first time in many years, there is relatively little going on by way of implementations of Icon for new platforms. The Apple Ilg, PRIME, and some models of the Cray are all we know of. Of corse, part of the reason is that Icon now has been implemented on most of the compters that have the capabilities it needs. Corrections to the Second Edition of the Icon Book We've fond a few mistakes and omissions in the second edition of Thelcon Programming Langage. These will be corrected when there's another printing, bt if yo have the first printing, yo may wish to note the following changes: Page 24, line 6: Change "prodces the vale of its left argment" to "prodces the vale of its right argment". Page 129: Add the following paragraph to the end of the text, before the exercises: The image of an integer that has more than approximately 25 digits is given showing the approximate nmber of digits, as in "integer(~100)". Page 287: Add i1 to i2 by i3 to the list of generators at the bottom of the page. Page 328, line 6: Change "star(string(8tlcase))" to "astar(string(&lcase))". Page 332, lines 28-30: Replace the procedre declaration for star(s) by procedre astar(s) sspend is (astar(s)!s) end Newsletters As annonced in the last 0\[ezvsfetter, we've started a new, more technical newsletter, called Wc[t,3lcon Analyst. The first two isses of the Analyst appeared in Agst and October. Pblication is on a bi-monthly basis and the third isse is schedled to appear in December. The first two isses of the Analyst contain articles on Version 8, getting started with Icon, expression evalation, syntactic pitfalls, memory monitoring, and timing Icon expressions. There also are programming tips and notes on advanced programming techniqes. We have pcoming articles on writing portable Icon programs, generators, large integers, memory tilization, and a series of articles on string scanning. At the same time, the freqency of pblication of The Icon 9{ezvsfetter will drop from three times a year to twice a year. This change reflects the shift of technical content from the 7{ezvsfetter to the Analyst and also the need to control costs the 9{ezvsfeUeris now sent free of charge to over 4,600 persons. If yo're really interested in Icon whether yo're a novice or an expert and especially if yo program in Icon yo shold seriosly consider sbscribing to

2 the Analyst. Every 12-page isse is crammed with sefl technical information, most of which is not available anywhere else. New sbscriptions to the Analyst normally start with the last pblished isse. We will start yor sbscription with an earlier isse if yo wish; jst make a note on the order form. Book Prices - From time to time we get complaints abot the prices of the Icon books. As we've said before, athors do not control the prices of the books they write; pblishers do We have long tried to get or pblishers to set lower prices for or books. We think the prices of many books in the compter field are inflated. We also think, in addition to the cost-vale qestion, that lower prices stimlate sales and are in everyone's best interest. Or argments, have, for the most part, been ignored. Another practice we find objectionable is increasing the price of a book freqently increases that seem to have li ttle jstification in terms of the pblishers' costs. Prentice-Hall increased the price of the first edition of The Icon Programming Langage one dollar every six months after its pblication. As a reslt, the original $18.95 price in 1983 had risen to $31.95 by the time it was replaced by the second edition in Inflation? It srely is! We thoght we'd won a small victory when Prentice- Hall decided to pblish the second edition at $ This price was at least less than that of the departing first edition, and the second edition is sbstantially larger also. Not a bargain, maybe, bt a better price than we expected. We were, then, flabbergasted to learn that the price of the second had been increased to $32 only two weeks after its pblication. It's hard to believe the new price is merely a coincidence. We sspect someone at the pblisher wold not tolerate an effective price redction. We asked for an explanation in Jne. We have yet to get an answer. Meanwhile, having been told the price was $29.95, we offered the book at in the last 9{ezi>sfetter ronding p a nickel to fit or format and as a token toward handling and shipping costs. It's or policy to honor or pblished prices for Icon material, regardless of increased costs to s, at least ntil we pblish a new price. So ntil now the Icon Project has absorbed the price increase. Jst as we went to press, we learned Prentice-Hall has increased its prices again. As yo'll see from the order form at the end of this 'Hg.zosfetter, we now place a limitation on how long or prices are garanteed. ICEBOL5 The first "ICEBOL" conference was held at Dakota State College in Madison, Soth Dakota in The primary focs of this conference was applications of the SNOBOL4 programming langage to compting in the Hmanities. Sbseqent conferences have expanded in scope, focsing on a broader area of interest and on other programming langages, notably Icon, Prolog and Lisp. Dakota State contines to host the conferences and now has niversity stats. Each conference has been better than the one before. ICEBOL4, held in October 1989, was notable for an increase in persons interested in Icon, ranging from novices to experts. The proceedings of this conference ran nearly 400 pages. ICEBOL5, officially titled the Fifth International Conference on Symbolic and Logical Compting, will be held April 18-19, Persons who receive this ivf zvsfetterwiw get an official annoncement and conference details. Persons who wish to sbmit papers for this conference shold contact Eric Johnson 114 Beadle Hall Dakota State University Madison, SD U.S.A. electronic mail: ERIC@SDNET.BITNET If yo want more information abot this conference, yo can address reqests as above or call (605) We expect ICEBOL5 to be the best yet and the Icon Project plans to be represented. We hope to see yo there. Downloading Icon Material Most implementations of Icon are available for downloading electronically: BBS: (602) FTP: cs.arizona.ed (cd /icon) ( or )

3 Second Icon Workshop In Jly 1988, members of the Icon Project and other persons closely associated with Icon met on the camps of Northern Arizona University in Hagstaff, Arizona. The 15 persons who attended the first workshop discssed langage design, implementation, and related aspects of the Icon programming langage. A second workshop was held in Jly 1990 at the same site. This time 21 persons attended. The sbjects discssed were similar to those of the first workshop, with new topics inclding the optimizing compiler for Icon and research presently nderway on an Icon programming environment with tools for visalizing program performance and behavior. A brief report on the second workshop is available free with any order of Icon material. Jst ask for "the second workshop report" or Icon Project docment IPD144. Update on the Icon Optimizing Compiler The Icon compiler described in the last isse of this Newsletter is now operational and most of the planned optimizations are implemented. Preliminary timing figres for complicated programs show speed improvements in the range of 1.5 to 3 times over the Icon interpreter. Some simple programs perform mch better than this nder the compiler. The optimizing compiler and the interpreter se essentially the same rn-time system. The compiler deals primarily with code generation for expression evalation, type checking, fnction bindings, and the allocation of space for temporary reslts. The compiler does not have any effect on most actal comptations. For example, the compiler does not toch operations like set and table look p and there are only minor differences in storage management between the two implementations. The optimizing compiler presently rns on a VAX nder UNIX 4.3bsd. We plan to port it to other 32-bit UNIX platforms, bt we have not yet set a date for possible distribtion. Prolcon Version 2.0 The Prolcon Grop has annonced Version 2.0 of Prolcon, an enhanced version of Icon for the Macintosh. Version 2.0 of Prolcon incldes all the featres of Version 8 of Icon and well as additional facilities for workingin the Macintosh environment. Notable among new featres in Prolcon 2.0 is an external fnction interface that provides access to HyperCard XCMDs and XFCNs, and well as "stand-alone" code resorces that can be sed to add extensions to Icon proper. The Version 2.0 distribtion also incldes an application for viewing Icon allocation histories in color. Prolcon 2.0 is schedled to start shipping in November. The price of Version 2.0 of Icon is $175 pls shipping. Edcational disconts and site licenses are available. Owners of Version 1.0 can pgrade for $35 pls shipping. Persons who prchased Version 1.0 after Agst 1,1990 only pay shipping. To order Prolcon 2.0 or get more information, contact Catspaw, Inc. P.O. Box 1123 Salida, CO U.S.A. (719)

4 The Icon Program Library The Icon program library consists of Icon programs and collections of procedres. The programs range from simple tilities to sophisticated text-generation applications. Most of the procedres are packages for specific applications, sch as string and strctre maniplation. In addition to providing sefl programs and procedres, the Icon program library also is an interesting sorce of examples of programming in Icon, which may be sefl to persons learning Icon. Version 8 of the Icon program library was released simltaneosly with the Version 8 of Icon. The Version 8 Icon program library contains 63 complete programs and 48 sets of procedres. Most of the material in the Icon program library is contribted by sers the work of several dozen programmers is represented in the Version 8 library. The Icon Project collects contribtions to the Icon program library, checks them to make sre they work, and packages them for distribtion. Since many of the programs are complicated, it isn't practical for s to test them extensively or to certify that they work entirely as advertised. Nonetheless, many of the programs in the library are in reglar se. Sbscribing to Library Updates We contine to get many contribtions to the Icon program library. We also make improvements and correct problems as they come p. It isn't practical for s to rebild the Icon program library every time there are changes and additions. Frthermore, the library gets larger and larger. All of this adds p to distribtion problems. We've decided to handle ftre distribtions of the Icon program library by a series of pdates to the basic Version 8 Icon program library. Updates are available by sbscription, mch in the manner of pdates to the sorce code for Icon. Updates inclde corrections to previosly distribted program material as well as new program material. Updates are provided only on MS-DOS diskettes in ASCII text format. Both 5.25" and 3.5" diskettes are available. Abot for pdates a year are planned, althogh the actal schedle will depend on available material and the resorces for assembling it. The cost for Icon program library pdates is for for pdates, inclding first-class mail in the United States, Canada, and Mexico. There is an additional charge of $10 per for pdates for first-class air mail delivery to other contries. Use the order form at the end of this 9(ezosfetter to sbscribe. Contribtions to the Icon Program Library We welcomesbmissionsof newmaterial to the Icon program library. Bt there are a few reqirements. Look at the example shown on Page 5 and the accompanying remarks. Contribted programs mst be accompanied by test data and an explanation of what the reslts of sing it shold be. Test files that are read as standard i np t a nd prodce reslts to standard otpt are best. For pack agesof procedres, a main program that links and tests them is reqired. In some cases, data read from stan dard inpt may not be appropriate. Send what yo think is best, bt realize that or resorces are limited and programs that are easy to test are more likely to get into the library and to get there sooner. (contined on page 6) Trie Icon 9{civstetter Madge T. Griswold and Ralph E. Griswold Editors The Icon T^ezvsfetter is pblished three times a year, at no cost to sbscribers. To sbscribe, contact Icon Project Department of Compter Science Gold-Simpson Bilding The University of Arizona Tcson, Arizona U.S.A. (602) FAX: (602) Electronic mail may be sent to: icon-project@cs.arizona.ed or...(net,allegra,noao}!arizona!icon-project ft h II TME UNIVERSITY OF ARIZONA TUCSON ARIZONA and The Bright Forest Company Tcson Arizona ) 1990 by Madge T. Griswold and Ralph E. Griswold All rights reserved.

5 Example Library Program Name: Title: Athor: * Date: deal.icn Deal bridge hands Ralph E. Griswold Jne 10,1988 This program shffles, deals, and displays hands in the game of bridge. An example of the otpt of deal.icn is S: H: D: C: S: KQ987 H: 52 D: T94 C: T82 3 T7 AKQ762 QJ94 S: A652 H: AKQ4 D: 3 C: A653 S: JT4 H: J9863 D: J85 C: K7 Options: The following options are available: * -tin Prodce n hands. The defalt is 1. -s n Set the seed for random generation to n. Different seeds give different hands. The defalt seed is 0. Links: options, shffle Heading information mst be in the format shown (it's processed by programs sed to maintain the library). A program description follows the heading. It shold explain what the program or collection of procedres does and be sfficiently detailed so that se is clear. In the case of a program, as shown here, command-line options shold be clearly evident. In the case of a collection of procedres, a prototype call for each procedre shold be given with an example of the reslts, if appropriate. Reqirements or restrictions, sch as linked files or operating-system dependencies, shold be given next in the form shown. link options, shffle global deck, deckimage, handsize, sitsize, denom, rank, blanker procedre main(args) local hands, opts deck := deckimage > string(&letters) initialize global variables handsize > sitsize := *deck / 4 rank := "AKQJT " blanker := repl(" ".sitsize) denom := &lcase[1 +:sitsize] The code itself shold begin with link, global, and record declarations. In the case of a program, the main procedre shold appear first, followed by other procedres, preferrably in alphabetical order. opts := options(args,"h+s+") hands := \opts["ht 11 &random := \opts["s"] every 1 to hands do display() end Display the hands procedre display() local layot, i static bar, offset Declare all local identifiers.

6 Icon Program Library (contined) Complex packages complicate distribtion, as do programs that read and write databases. In fact, we have several sch programs that have never been distribted, simply becase we haven't figred ot how to pt them together so that they wold rn on a variety of different systems. Similarly, packages that combine Icon programs with programs written in other programming langages are not likely to make it into the library. Contribtions to the Icon program library mst be free of any restrictions on distribtion. We do not accept copyrighted programs, regardless of any accompanying prose that appears to allow nlimited copying. Finally, we reserve the right to decide what material to inclde in the library. The main considerations are qality, seflness, compliance with the library format, and sbmission of adeqate test data with the contribtion. Sbmissions that dplicate fnctionality that already exists in the library generally will not be accepted. All sbmissions are acknowledged bt decisions on inclsion in the library may not be made immediately. If yo've sbmitted material in the past that's not appeared in the library, yo may wish to ask abot its stats we have a lot of material from past years that lacks adeqate docmentation and test programs. And in some cases we've lost toch with the persons who sbmitted material. Of corse, we give fll credit to the athors of program material that's inclded in the library. Even if yo don't have anything to contribte to the library, yo may find a bg or make an improvement to the library. By all means let s know abot sch things. FTP Access to Icon Exectable Files As mentioned in the last 'Hg.zosfetter, most Icon program material and some docmentation can be obtained electronically. If yo have access to FTP, yo now can also get exectable files for several platforms withot having to download and compile the sorce code. Do an anonymos FTP to cs.arizona.ed and cd to /icon/v8/binaries. There are sbdirectories for different operating systems and, in these, frther sbdirectories for different compters. Be sre to se the binary (image) mode for file transfer of exectable files. Be aware that binary compatibility is problematical for some systems. We can't garantee that the exectable files we have in or FTP area will work as expected on other systems. We also welcome contribtions of other exectable files for Version 8 of Icon. Yo can pload to or FIT area by doing an anonymos FTP as described above, followed by a Cd to /incoming. Yo can then pt tiles in the area. If yo do this, send electronic mail to iconproject@cs.arizona.ed with an explanation of what yo've ploaded. Material in that area isatomatically removed after five days, so we need to know when it arrives. From Or Mail Is Icon available on CD ROM? No. Prodcing a CD- ROM master is a fairly complicated and expensive process, and different formats are reqired for different systems. There's not enogh demand for an Icon CD-ROM yet to jstify prodcing one. I see Idol, the object-oriented version of Icon, is inclded in the Icon program library, bt there's no docmentation for it. How am I spposed to se it if there's no docmentation? Althogh we don't distribtea printed copy of the Idol ser's manal with the Icon program library, there's a machine-readable version, sitable for printing, in the Idol portion of the library. I've been experimenting with the new Version 8 fnctions variable(s) and name(v). I thoght they'd be inverses, bt while name(variable(s)) seems always to prodce s, variable(name(v)) doesn't prodce v nless it's an identifier. Is this a bg? No, it's not a bg. It's a "featre", as they say. In the case of a strctre reference like L[10], the name prodced is not niqe it's jst "list[10]". There's no way to tell which list it is. Granted, lists and other strct res have serial nmbers and yo might expect the serial nmber to be part of the string retrned by name(v), ths providing a niqe identification. The problem is in the implementation of strctres in Icon; there's no practical way to get the serial nmber of a strctre from a reference to an element in it. Incidentally, variable(s) works for the names of keywords as well as identifiers. I see The Bright Forest Company mentioned in connection with Icon from time to time. What's its relationship to the Icon Project? The Bright Forest Company is a small, privately held corporation whose main prpose is to develop com

7 mercial implementations of Icon. Madge Griswold is president of The Bright Forest Company and Ralph Griswold is its vice president. The Bright Forest Company and Catspaw, Inc. have a joint ventre, The Prolcon Grop, that markets an enhanced version of Icon for the Macintosh. The Bright Forest Company also contribtes to The Icon 9(ezvsfetterand be,3)con (Anatgst. The Bright Forest Company does not, however, receive any income from the Icon Project. I have yor two technical reports on programming in Icon, one on generators written in 1985 and one on co-expressions written in Are there any other reports in this series or any more planned? We originally planned several reports on varios aspects of programming in Icon, inclding ones on string scanning and programming with strctres. We now are pblishing material of this kind in '9Ihe,3lcon (Analrret. No frther technical reports of this kind are planned. Yo charge a lot of overseas air mail shipping. Woldn't it be better to ship by srface mail nless someone is in a real rsh? Yes, overseas air mail shipping is expensive. We only charge what it costs s, on the average (rates vary somewhat from contry to contry with little relationship to the distance involved). The troble with srface mail is that it is very slow and somewhat nreliable. We once sent a tape to India by srface mail and it took 11 months to arrive. It jst isn't practical for s to deal with the problems related to srface mail (like handling inqiries abot whether shipments are lost). Most of or overseas cstomers prefer air delivery and accept the fact that it's costly. I was sorry to see yo replaced troff versions of UNIX Icon docments with PostScript files in Version 8.1have troff bt not a PostScript printer. Distribting docmentation in a form sitable for copying has always been a problem for s, since different sites have different software and printing facilities. We've stopped distribting troff sorce for docments becase they reqire proprietary macro packages that many sites do not have and which we are nable to inclde. We realize that not all sites have access to a PostScript printer, bt those that do can get high qality, correctly formatted Icon docments. There's another consideration: While we still se troff for many docments, troff is antiqated, awkward, and limited compared to crrent desktop pblishing systems. Many of or docments (inclding this tyzsfettef) are now prepared sing Alds PageMaker on a Macintosh. PostScript otpt from this system can be distribted in the same way as PostScript for troff. others, depending on how mch material yo have. Or do yo jst wait ntil yo have 12 pages worth? If so, doesn't this sometimes delay the newsletter? The 12-page length of the 9{ezvsfetter (and the <Ana- Igsst) is a conseqence of printing constraints. The best printing and binding method available to s at The University of Arizona ses two-p printing and saddle stitching. Two-p means that two pages are photographed at one time to make a plate for offset printing on an ll-by-17" sheet of paper. This sheet is then printed on the back with two more pages, for a total of for pages. Three of these sheets are collated, stitched, and folded to make p or 12-page, 8-1/2 by 11" newsletter. Saddle sti tching is an old term for fastening the signatres at the center fold between adjacent pages. Or printer ses staples, not thread as in original saddle stitching. In any event, center stapling prodces a mch nicer reslt than corner or edge stapling the sheets lie flat when a newsletter is opened. It's the two-p method of printing that leads to or 12- page format. The nmber of pages mst be a mltiple of for. We sally have too mch material for eight pages and not enogh for 16. To be honest, we sometimes have to scramble to fill p 12 pages and still meet or pblication schedle. More often, we have too mch material and defer or leave ot some. For example, if we hadn't had a sbstantial hole in this part of the 9{ezvsfetter, we woldn't have printed this qestion and answer. Graphics are handy too for making things come ot right, especially since it's easy to re-size and move them in or desktop pblishing system. Incidentally, the second edition of The Icon Programming Langage was printed 8-p, in 16-page "signatres". We prodced camera-ready typeset copy for the book and in or contract the pblisher stiplated exactly 384 pages, inclding front and end matter (24 16-page signatres). It was a bit scary writing a book that had to come ot to an exact nmber of pages when typeset. By some kindly qirk of fate, it did come ot exactly right on the first attempt, withot any ctting or filling. There! That fills the hole nicely. I've been wondering why all recent Icon newsletters have be exactly 12 pages long. I'd think some wold be longer than

8 An Oral History of Icon Editors' Note: The following article was contribed by David S, Cargo, who attended the Second Icon Workshop. See the article on page 3 and the box to the right. I had become active in the se of Icon and its promotion after reading The Icon Programming Langage by Ralph E. Griswold and Madge T. Griswold and acqiring Icon 5.9 for MS-DOS. I sed Icon to write several tilities for data base maniplation and analysis while maintaining a large mailing list. I pgraded to later versions of Icon for MS-DOS and boght Icon for VAX/VMS for se where I worked at Honeywell Test Systems and Logistics Operations. In informally taghta small gropof people within Honeywell abot Icon. Eventally, some of these people went on to write their own Icon applications. Once I became aware of an Internet mailing list called icon-grop, I joined a commnity of Icon sers who kept in toch throgh electronic mail. The Internet greatly facilitates sage of Icon. It provides a medim for distribtion of Icon implementations as well as a means for commnicating qestions and answers. When I went to work for Cray Research in 1990,1 began to work to get Icon implementations for Cray Research systems. To date, I have been able to persade someone to develop Icon for the Cray-2. A version for Cray Y-MP will be available at an indeterminate date. After I received an invitation to the second Icon workshop, I realized what a broad cross-section of people involved with Icon wold be there. I decided that this was an opportnity to collect oral history interviews recording the history of the Icon Project. I approached Professor Ralph Griswold and Arthr Norberg (Director of the Charles Babbage Institte) to get their permission to collect interviews nder the aspicies of the Charles Babbage Institte. After editing and review, the interviews will join the oral history collection of CBI. The emphasis of the interviews was on the methods sed to keep the Icon Project operating continosly and prodctively over sch a long period of time. I believe the Icon Project makes a sbstantial and lasting contribtion to research in the design and implementation of programming langages for non-nmeric applications. The Icon Project also has some parallels with other niversity-rn projects that have prodced worthwhile, sefl software available at little or no cost to sers. Two other examples that come readily to mind are TEX, the typesetting langage prodced by Donald Knth at Stanford, and Kermit, a file transfer protocol and many implementations that are managed by Co- The interviews at the second Icon programming langage workshop were condcted for the Charles Babbage Institte. The Charles Babbage Institte is dedicated to promoting the stdy of the history of information processing. The institte is located on the Minneapolis camps of the University of Minnesota. CBI was fonded in 1979 to foster the research of the history of the "Information Age." Becase the Information Age has developed in less than a single life-span, there is a niqe opportnity to docment its social, economic, and technical aspects. CBl's goal is to lead the way in collecting the knowledge and docmentation possessed by key pioneering individals and pblic and private instittions. Historical analysis of firsthand acconts and primary sorce materials provides a niqe opport nity to enhance the qality of nderstanding of the Information Age. CBI has several programs for promoting historical research into the history of information processing. CBI condcts historical research itself. Topics ha ve inclded development of the compter indstry, scientific comptation, the role of government in compting, and technical developments. The Institte collects and makes available a col lection of historical materials solicited from practitioners and organizations in the field. CBI also gathers information abot collections held in other repositories in both indstrial and academic archives. The most heavily reqested materials from CBI are photographs. The CBI photographic archives contain more than 3,000 photographs, inclding many of machines and people predating CBI has collected oral interviews with over two hndred pioneering individals in the information processing field. CBI staff members are contining to collect interviews, especially with leading researchers and corporate exectives who were responsible for developing strategies for their com panies' involvement in information processing. CBI has several other activities that promote research into the history of information processing. It maintains data bases that identify historically significant materials, awards fellowships to gradate stdents whose dissertations address aspects of the history of information processing, hosts and cosponsors conferences and lectres that provide historical perspective on information processing, and pblishes a newsletter and reprints of difficlt-toobtain works of historical significance. David S. Cargo

9 lmbia University. I interviewed Professor Ralph E. Griswold and Madge T. Griswold. I also interviewed for former or crrent gradate stdents who worked on Icon for Prof. Griswold: Stephen B. Wampler (now with the College of Engineering at Northern Arizona University), William H. Mitchell (now with Snqest Information Systems), Gregg M. Townsend and Kenneth Walker (both with the Department of Compter Science at The University of Arizona). Finally, I interviewed two people who first adapted Icon to new systems, Robert E. Goldberg (with Dewar Information Systems Corporation), and Cheyenne Wills (who acted as an independent consltant for the Icon Project). The interviews cover many of the signficant events in the history of the Icon Project: the first version of Icon in C (Stephen Wampler), the first version of Icon with detailed instrctions for porting to new systems and the first version with greatly redced reqirements for assembly langage spport (William Mitchell), the first version of IconforMS-DOS (Cheyenne Wills), and the first version of Icon for VAX/VMS (Robert Goldberg). While Icon might be a tool less widely sed than TgX or Kermit, the Icon Project has continally demonstrated that excellent software can come ot of academic environments and earn a significant place in the real world of compter applications. I hope that collecting these oral histories will help secre a place for Icon in the history of programming langages and information processing. way that is natral for Icon and that tilizes the capabilities of Icon (sch as generators). One of the tools planned for the Icon programming environment is a program exection monitor. In one sense, this is jst a fancy name for a debgger. We expect, however, to prodce a tool with sbstantially greater capabilities than are fond in most debggers, so we're avoiding the "D word", lest it give the wrong impressions. Visalization has a high priority in the tools we are developing. We want tools that can present large amonts of complex information in ways that the hman mind can comprehend. This sggests an orientation toward right-brained, pattern-oriented presentations that concentrate on relationships rather than the more convention left-brained langage-oriented detailed labelings and listings. Color is an essential component of the tools we plan to develop. We reqire display devices that can handle at least 256 colors. We can't show yo here what we have in mind, bt if yo've ever watched Icon's memory-monitoring displays, yo'll know what we mean. We're jst starting on this research project. Or goals are ambitios and it will take a sbstantial amont of time to achieve them. We'll report on or progress with the Icon programming environment from time to time in this 'Xg.zosfetter. We also want to emphasize that this is a research project, not prodct development. We have no plans at present to distribte the software that we may develop. An Icon Programming Environment Work is nder way at The University of Arizona on a programming environment for Icon. This is a research project that is primarily concerned with the design of high-level tools for program development, debgging, and measrement. Mch of the environment will be written in Icon itself. An enhanced version of Icon is being developed for se in this project. The two main enhancements are windowing capabilities and the ability to rn several Icon programs nder the same interpreter. Sch programs will be able to commnicate with each other. We have chosen X-Windows for the windowing environment. This choice was made largely becase the research is being done in a UNIX environment in which X has general spport. The Icon interface to X spports only a limited sbset of X's capabilities. The interface is at the Xlib level, bt it does not mimic Xlib precisely; rather, it is cast in a Bg in Version 8 of Icon We've jst fond a bg in Version 8 that yo're nlikely to enconter, bt that is still sfficiently serios that we're mentioning it. The bg occrs when an empty list is formed by copying an empty list, forming an empty list section, or concatenating two empty lists. An attempt to psh or pt onto sch a list may overwrite other data or case a memory violation. This bg was not fond for a while, since creating an empty list in one of these ways is not common. The fix to the sorce code for Icon is simple, and persons who sbscribe to sorce pdates will get it when the next pdate is released. Updating the exectable binary files we distribte is not so simple. We don't even have the capability locally to do it for all systems. So, if yo're sing Version 8 of Icon and yor program may form a list in one of the three ways mentioned above, yo need to change yor code to avoid the possibility.

10 Ordering Icon Material What's Available There are implementations of Icon for several personal compters, as well as for CMS, MVS, UNIX, and VMS. Sorce code for all implementations is available. Program material is accompanied by installation instrctions and sers manals in printed and machinereadable form. There also is a program library that contains a large collection of Icon programs and procedres, as well as an object-oriented version of Icon that is written in Icon. In addition to sers manals that are inclded with program material, there are three books and two newsletters abot Icon. Icon Program Material The crrent version of Icon is 8. All the program material here is for Version 8. All program material is in the pblic domain except the MS-DOS/386 implementation of Icon, which is a commercial prodct that carries a standard software license. Personal Compters: Exectables, sorce code, and the Icon program library for personal compters are provided in separate packages. Each package contains docmentation in printed and machine-readable form. Note: Icon for personal compters reqires at least 640KB of RAM; it reqires more on some systems. CMS and MVS: The CMS and MVS packages contain exectables, sorce code, test programs, the Icon program library, and docmentation in printed and machine-readable form. UNDC: The UNIX package contains sorce code bt not exectables, test programs, related software, the Icon program library, and docmentation in printed and machine-readable form. UNIX Icon can be configred for most UNIX systems. Note: exectablesforxenix and the UNIX PC are available separately. VMS: The VMS package contains object code, exectables, test programs, the Icon program library, and docmentation in printed and machine-readable form. Porting: Icon sorce code for porting to other compters is distribted on MS-DOS format diskettes. There are two versions, one with a flat file system and one with a hierarchical file system. Update Sbscriptions: Updates to the Icon sorce code and the Icon program library are available by sbscription. Sorce-code pdates are distribted on MS-DOS diskettes in ARC format for hierarchical file systems, and are sitable for compilation nder MS-DOS or for porting to new compters. Each pdate sally provides a completely new copy of the sorce. A sorcecode sbscription provides five pdates. Updates are issed abot three times a year. Icon program library pdates are distribted on MS- DOS diskettes in plain ASCII format. A library sbscription provides for pdates. Updates are issed abot twice a year. Docmentation In addition to the installation gides and sers manals inclded with the program packages, there are three books on Icon. One contains a complete description of the langage, the second describes the implementation of Icon in detail, and the third is an introdctory text designed primarily for progra mmers in the Hmanities. There are two newsletters. The Icon 9{tzvsftttercontains news articles, reports from readers, information of topical interest, and so forth. It is free, and is sent atomatically to anyone who places an order for Icon material. There is a nominal charge for back isses of the 'Hpzvsfetter. Tr«* ^Elcon JVnalgat contains material of a more technical natre, inclding in-depth articles on programming in Icon. There is a sbscription charge for the JVnalgat. Payment Payment shold accompany orders and be made by check, money order, or credit card (Visa or Master Card). The minimm credit card order is. Remit tance mst be in U.S. dollars, payable to The University of Arizona, and drawn on a bank with a branch in the United States. Organizations that are nable to pre-pay orders may send prchase orders, sbject to approval, bt there is a $5 charge for processing sch orders. 10

11 Prices The prices qoted here are good ntil December 31,1990. After that, prices are sbject to change withot frther notice. Contact the Icon Project for more crrent pricing information. Ordering Instrctions Media: The following symbols are sed to indicate different types of media: o H 9-track magnetic tape DC 300 XL/P cartridge 360K 5.25" diskette 400K 3.5" diskette 800K 3.5" diskette All cartridges are written in raw mode. All diskettes are written in MS-DOS format except for the Amiga, the Atari ST, and the Macintosh. CMS and MVS tapes are available onlyat 1600bpi. WhenorderingUNIX or VMS tapes, specify 1600 or 6250 bpi (1600 bpi is the defalt). When ordering diskettes that are available in more than one size, specify the size (5.25" is the defalt). Shipping Charges: The prices listed inclde handling and shipping by parcel post in the United States, Canada, and Mexico. Shipment to other contries is made by air mail only, for which there are additional charges as noted in brackets following the price. For example, the notation means the item costs and there is a $5 shipping charge to contries other than the United States, Canada, and Mexico. UPS and express delivery are available at cost pon reqest. Ordering Codes: When hilling ot the order form, se the codes given in the second colmn of the list to the right (for example, AME, ATE,...). Icon Exectables Amiga Atari ST MS-DOS MS-DOS/386 Macintosh (MPW) OS/2 UNIX PC Xenix Xenix/386 Icon Sorce Amiga Atari ST MS-DOS and OS/2 Macintosh (MPW) Porting (flat, ASCII) Porting (hier., ARC) Sorce Updates (5) Icon Program Library Amiga Atari ST MS-DOS and OS/2 Macintosh (MPW) Porting (ASCII) UNIX (cpio) Library Updates (4) Complete Systems CMS MVS UNIX (cpio) UNIX (cpio) UNIX (cpio) UNIX (tar) UNIX (tar) VMS Books AME ATE DE DE-386 ME OE UE XE XE-386 AMS ATS DS MS PFS PHS SU AML ATL DL ML PL UL LU CT MT UT-C UC-C UD UT-T UC-T VT The Icon Programming Langage (2nd ed.) The Implementation of Icon + pdate Icon Programming for Hmanists + disk Newsletters Tli] H(2)or HorU HorU HorU H(2)or HorU H(2)or H(5)or H(2)or H(2)or on) HorU U H(2)or U H(2)or U HorU o m H(9)or o m O LB IB HB The Icon tyzvsfetter (all back isses, 1-33) INC The Icon 9{exvsfetter(single isses, each) mrje,31am.analgat (1 year, 6 isses) 11 INS IA $20 $25 $20 H(2) $40 $20 U U $50 $45 H(4) $40 $45 $34 $45 $1 $25 [$8] [] [$12] [$8] [$13] [$14] [$0]

12 Order Form Icon Project Department of Compter Science Gold-Simpson Bilding The University of Arizona Tcson AZ U.S.A. Ordering information: (602) Fax: (602) name address city (contry) O check if this is a new address state telephone zipcode qty. code description price shipping* total Make checks payable to The University of Arizona The sales tax for residents of the city of Tcson is 7%. It is 5% for all other residents of Arizona. sales tax sbtotal ( Arizona residents) extra shipping charges* prchase-order processing other charges Payment Visa MasterCard O check or money order total I hereby athorize the billing of the above order to my credit card: ( minimm) card nmber exp. date name on card (please print) signatre 'Shipping charges apply only to addresses otside the United States, Canada, and Mexico 12