TweetFollow Us on Twitter

Jun 90 Letters
Volume Number:6
Issue Number:6
Column Tag:Letters

Parse Table Correction

By Kirk Chase, Editor, MacTutor

Parse Table Correction

Kirk Chase

MacTutor

Unfortunately, Clifford Story’s second part in his Language Translation Series was missing the parse table. Here it is for you now:

Dialogs, the easy way

Neil Ticktin

Truin Software

I was glad to see that dialogs are now getting some press. I wanted to make sure, though, that your readers connect dialogs with Extender DialogHandler™ by Invention Software. First, there is a review by David Kelly on DialogHandler in the January, 1990 issue of MacTutor.

In the April, 1990 article on extending modal dialogs, Paul Potts talks about default bold outlining, key equivalents and default items.

DialogHandler takes care of all of these things automatically for you. In your article on Messenger, you speak about placing dialogs, icons, multiple buttons, character equivalents, and adding filters. Again, DialogHandler takes care of all of these things as well -- all automatically. In short, DialogHandler handles push buttons, multiple sets of radio buttons, check boxes, counter items, icons and pictures with animation, display text items, pop-up menus, pull down menus, “pick lists” (list manager style), and string, integer, long integer, and real “flavors” of edit and static text. All number conversion, on-the-fly character filtering, cut/copy/paste support, and key equivalents are taken care of automatically.

DialogHandler now supports modeless dialogs. In addition, almost every item can have a “user hook” associated with it. In other words, if you want a push button to do something special, you can write a procedure to do that and pass a pointer to that procedure to DialogHandler. DialogHandler, in turn, will call your routine when the item is hit.

For example, take a simple dialog that asks for an integer between -100 and 100, has a bold outlined OK button, a Cancel button, on-the-fly character filtering (the user can’t enter a bad character), full cut/copy/paste support, range checking with alert and handling of the ok and cancel buttons. Using DialogHandler, you can write the support code for this dialog with 6 lines of code.

In summary, if you are doing dialogs, modal or modeless, you can do them in 5-10% of the time using Extender DialogHandler™ from Invention Software at 313-996-8108. It will pay for itself on the first dialog. As you already may know, MacTutor is also selling DialogHandler in the mail order store.

MultiFinder Detection

Ajay Nath

Oakland Gardens

Daniel Allens excellent book, “On Macintosh Programming: Advanced Techniques”, shows a quick way (on p. 160) to find out if MultiFinder is running. Simply examine the long word at $B7C which is called “Twitcher2”, if its less than 0 then MultiFinder isn’t running. I have a feeling that somebody at Apple didn’t read his book too carefully since I don’t think they’d want us to know this.

cdevShell

Charles Dyer

Jamaica, West Indies

I am writing about that cdevShell.p article in February, 1990 MacTutor. I finally got it all entered and tried to test it out, but then I found drumroll, please BUGS. Some of them were typos, but those were easily fixed. However, I still get the ever-popular ID=2 and ID=28 bombs even after I had corrected all of my spelling errors. So I used TMLPascal’s TMLPasRef utility to try to track who did what/where, and guess what: a lot of items are initialized but never used. In particular, the variables totalItems, p, c, tempD, and r in the procedure startupCdev are never used anywhere. It appears that a line or two may have been left off. And those were only the more obvious and easier to find examples. After I found them, I went through the source checking every case where PasRef said that a variable had been used once, and found several others. I also checked the .r file, and noted that there doesn’t seem to be a DLOG or an ALRT for DITL -15999.

Tracking would have been easier if only Mr. Hoddie hadn’t used so many cryptic variable names. I mean, in startupCdev the variable c is of type ControlHandle. A little further on, there is another c which is an INTEGER. Would it have been so difficult to use theControl and counter, respectively? The whole programme is peppered with single-character variables: e, i, j, p, r I haven’t seen so many single-character variables in one place since I stopped using BASIC on an Apple II. Variable names like dP, tempD, and rH don’t help either. It’s not so bad if the thing works right the first time, but

In the past, if I had a problem, when I translated a program over from Pascal to Modula-2 and things didn’t work, I wouldn’t know if it was because so obscure difference between Pascal and Modula-2 or if it was just that I did something wrong. Thanks to TML, if it doesn’t work and I can’t find any difference between my code and what’s in the magazine, I’d say something is wrong with the published code. In any case, I’ve gone through my code several times and cannot see where I’ve gone wrong. It might still be something I did, so I’ll try again, but in the meantime, I’d like to know if anyone else has had any problems with cdevShell.p.

I now use TML Pascal II, as SemperSoft seems to have bitten the dust. I would like to get another Modula-2 package, but no-one else seemed to have an MPW Modula-2 package available. Having shelled out all that cash for MPW in the first place, I am not going to give up on it without a fight. I’ll even get C-ugh-if I have to. Actually, what with UNITs and some of the other extensions, TML Pascal is almost Modula-2 anyway. The .o and executable files that TML makes are a little bigger than those made by SemperSoft Modula-2, but TML is faster and doesn’t give weird problems when you’re trying to build cdevs and INITs. The biggest problem so far has been the Show Icons LDEF demo program from the TML Source Code Library crashes and burns under MultiFinder. I haven’t gotten around to writing them about that yet.

[I have check the printed code against the original source code, and I could not see a line missing in startupCdev. I have had no complaints, other than yours, about cdevShell.p. I ask if anyone else has to write a letter to MacTutor. On the good side, Metrowerks has Modula-2 for MPW at $150. Their phone number in the USA is 514-458-2018; their FAX number is 514-458-2010.-ed]

MPW Pascal Compiler

Richard H. Winkler

Boulder, CO

We have discovered a bug in the MPW Pascal compiler which has remained constant from version 2.02 through version 3.1. The bug arises when the stack frame in a procedure exceeds 32k bytes in size. Two Pascal programs used to test this bug differ only in stack frame size, the program ‘lgstkfrmst’ had added to it a second array, z2: ARRAY[1..7000] OF REAL, which caused the stack frame to grow beyond 32k. As one would expect, the addressing strategy for all stack frame variables which are normally addressed indirect through A6 is altered such that A6 is moved to A0, the variable offset is added to A0, and the variable is then addressed indirect through A0. The assembly code produced from ‘lgstkfrmst’ produces an instruction:

;1

PEA$252A(A6)

which should in fact be the set of instructions:

;2

MOVEA.L A6,A0
ADDA.L  $FFFF252A, A0
PEA(A0)

This is a particularly unusual error in that the lower half of the address is correct. Had the compiler used proper (A6) addressing one would have expected something other than $252A. In particular one would have expected -$6D6C as in the assembly listing of ‘smstkfrmtstcd’, the smaller stack frame test code. This error is believed to occur following calls to transcendental function other than _LN.

As a historical note, let me add the following. I suspect that what is now the MPW Pascal compiler was originally developed by Silicon Valley Software for earlier 68000 based machines. In particular, I believe that this was the same Pascal compiler used for the ill fated IBM 9000 computers. I have worked extensively with 9000’s and base this conclusion on the fact that the manual included with version 2.02 of the MPW complier was word for word identical, down to the page breaks, with the Pascal manual supplied with the IBM 9000. With the 9000 compiler, we also had a compiler bug associated with the stack frame growing beyond 32k bytes. In particular there was a range of stack frame sizes from 32000 bytes to somewhere greater than 32768 bytes where the stack frame pointer, A6, was set point to the load point of the system library rather than to the stack frame when a subroutine was entered. This bug was fixed by IBM (Silicon Valley Software?) in version 2.0 of the compiler, but I find it an interesting coincidence that the MPW compiler has a bug which arises under similar circumstances surrounding the stack frame.

 
AAPL
$524.75
Apple Inc.
-6.95
MSFT
$39.69
Microsoft Corpora
-0.30
GOOG
$526.94
Google Inc.
-7.87

MacTech Search:
Community Search:

Software Updates via MacUpdate

MacFamilyTree 7.1.6 - Create and explore...
MacFamilyTree gives genealogy a facelift: it's modern, interactive, incredibly fast, and easy to use. We're convinced that generations of chroniclers would have loved to trade in their genealogy... Read more
EtreCheck 1.9.9 - For troubleshooting yo...
EtreCheck is a simple little app to display the important details of your system configuration and allow you to copy that information to the Clipboard. It is meant to be used with Apple Support... Read more
TeamViewer 9.0.28116 - Establish remote...
TeamViewer gives you remote control of any computer or Mac over the Internet within seconds, or can be used for online meetings. Find out why more than 200 million users trust TeamViewer! Free for... Read more
Viber 4.1.0 - Send messages and make cal...
Viber lets you send free messages and make free calls to other Viber users, on any device and network, in any country! Viber syncs your contacts, messages and call history with your mobile device,... Read more
Apple iOS 7.1.1 - The latest version of...
The latest version of iOS can be downloaded through iTunes. Apple iOS 7 brings an all-new design and all-new features. Simplicity Simplicity is often equated with minimalism. Yet true simplicity is... Read more
1Password 4.3 - Powerful password manage...
1Password is a password manager that uniquely brings you both security and convenience. It is the only program that provides anti-phishing protection and goes beyond password management by adding Web... Read more
Lens Blur 1.3.0 - True out-of-focus boke...
Let Lens Blur transform your existing photo into true SLR-quality out-of-focus bokeh effect! Everyone needs a gorgeous personalized background for a social profile, blog, Web/UI design, presentation... Read more
VMware Fusion 6.0.3 - Run Windows apps a...
VMware Fusion allows you to create a Virtual Machine on your Mac and run Windows (including Windows 8.1) and Windows software on your Mac. Run your favorite Windows applications alongside Mac... Read more
BitTorrent Sync 1.3.93 - Sync files secu...
BitTorrent Sync allows you to sync unlimited files between your own devices, or share a folder with friends and family to automatically sync anything. File transfers are encrypted. Your information... Read more
Tweetbot 1.5.1 - Popular iOS twitter cli...
Tweetbot is a full-featured OS X Twitter client with a lot of personality. Whether it's the meticulously-crafted interface, sounds and animation, or features like multiple timelines and column views... Read more

Latest Forum Discussions

See All

Leo's Fortune (Games)
Leo's Fortune 1.0.2 Device: iOS Universal Category: Games Price: $4.99, Version: 1.0.2 (iTunes) Description: Leo’s Fortune is a platform adventure game where you hunt down the cunning and mysterious thief that stole your gold.... | Read more »
iOOTP Baseball 2014 Edition Review
iOOTP Baseball 2014 Edition Review By Carter Dotson on April 23rd, 2014 Our Rating: :: SOLID CONTRACTUniversal App - Designed for iPhone and iPad The long-running baseball simulator returns to mobile with a much-improved entry in... | Read more »
148Apps Live on Twitch: Soccer Rally 2 w...
Soccer Rally 2 from IceFlame Games officially releases on Thursday, bringing perhaps the most realistic car soccer action to the App Store since the original released. David Deacon of IceFlame Games will join us on our Twitch channel to talk about... | Read more »
NightCap Pro Review
NightCap Pro Review By Jennifer Allen on April 23rd, 2014 Our Rating: :: NIGHT TIME SNAPPINGUniversal App - Designed for iPhone and iPad Taking photos in low light conditions has always been tricky, but NightCap Pro has just made... | Read more »
Plague Inc. has Mutated Yet Again – We’r...
Plague Inc. has Mutated Yet Again – We’re All Doomed Even More than Usual Posted by Rob Rich on April 23rd, 2014 [ permalink ] Universal App - Designed for iPhone and iPad | Read more »
Intake from Cipher Prime Coming to iPad...
Cipher Prime’s Inake is coming to iPad on May 1, as exclusively revealed yesterday on our Twitch channel. | Read more »
Gusto Email App Review
Gusto Email App Review By Jennifer Allen on April 23rd, 2014 Our Rating: :: POWERFUL SEARCHINGiPhone App - Designed for the iPhone, compatible with the iPad Focusing on making it easy to browse files and photos attached to your... | Read more »
New Update Adds Two More Cars to Fishlab...
New Update Adds Two More Cars to Fishlabs’ Sports Car Challenge 2 Posted by Rob Rich on April 23rd, 2014 [ permalink ] Universal App - Designed for iPhone and iPad | Read more »
What’s Up with Readdle? – The Verge Exam...
What’s Up with Readdle? | Read more »
Knight Saves Queen Review
Knight Saves Queen Review By Jennifer Allen on April 23rd, 2014 Our Rating: :: PUZZLING MASH UPUniversal App - Designed for iPhone and iPad Mixing up puzzle elements with Chess-based sensibilities is a fun move for this simplistic... | Read more »

Price Scanner via MacPrices.net

iPad Sales “Lull” A Reality Correction Of Unm...
I have lots of time for Jean-Louis Gassée, the former Apple Computer executive (1981 to 1990) who succeeded Steve Jobs as head of Macintosh development when the latter was dismissed in 1985. Mr.... Read more
Apple Makes OS X Betas Available To All – Wit...
Apple’s OS X Beta Seed Program, which lets you install the latest pre-release builds, try it out, and submit your feedback, is now open to anyone who wants to sign on rather than to developers and... Read more
Apple Releases iOS 7.1.1 Update
The latest iOS 7.1.1 update contains improvements, bug fixes and security updates, including: • Further improvements to Touch ID fingerprint recognition • Fixes a bug that could impact keyboard... Read more
Logitech Announces Thinner, Lighter, More Fle...
Logitech has announced an update to its Ultrathin for iPad Air, iPad mini and iPad mini with Retina display, improving the flexibility and design of its award-winning predecessor with an even thinner... Read more
Logitech Introduces Hinge, Big Bang and Turna...
Logitech has announced expansion of its tablet product line with three new cases – the Logitech Hinge, the Logitech Big Bang and the Logitech Turnaround – each for the iPad Air, iPad mini and iPad... Read more
WaterField’s Rough Rider Leather Messenger Ba...
WaterField Designs have announced the new 15-inch size of their popular Rough Rider leather messenger bag, a vintage-looking bag that combines Old West charm and ruggedness with distinctly modern... Read more
New Mac Pro on sale, save $100 on the 4-Core...
J&R has the new 4-Core Mac Pro in stock today and on sale for $2899 including free shipping plus NY sales tax only. Their price is $100 off MSRP, and it’s the lowest price available for this... Read more
Apple refurbished iMacs available for up to $...
The Apple Store has Apple Certified Refurbished 2013 iMacs available for up to $300 off the cost of new models. Apple’s one-year warranty is standard, and shipping is free. - 27″ 3.4GHz iMac – $1699... Read more
Updated iPad Price Trackers
We’ve updated our iPad Price Tracker and our iPad mini Price Tracker with the latest information on prices and availability from Apple and other resellers. Using a mobile device? We’ve also updated... Read more
Everything You Wanted To Know And Probably Mo...
Macworld UK’s Lou Hattersley takes a look inside Apple’s A7 System On Chip (SoC) , noting that its processor module is much more powerful than other smartphone chipsets. He notes that the A7 was a... Read more

Jobs Board

*Apple* Solutions Consultant (ASC) - Apple (...
**Job Summary** The ASC is an Apple employee who serves as an Apple brand ambassador and influencer in a Reseller's store. The ASC's role is to grow Apple Read more
Position Opening at *Apple* - Apple (United...
…customers purchase our products, you're the one who helps them get more out of their new Apple technology. Your day in the Apple Store is filled with a range of Read more
*Apple* Solutions Consultant (ASC) - Apple (...
**Job Summary** The ASC is an Apple employee who serves as an Apple brand ambassador and influencer in a Reseller's store. The ASC's role is to grow Apple Read more
*Apple* Inc. Research Data Specialist - Appl...
…of Worldwide Market Research & Intelligence. The team is responsible for conducting Apple branded consumer market research. It is also responsible for analyzing data Read more
*Apple* Automotive Parts Department position...
Apple Automotive is one of the fastest growing dealer…and it shows. Consider making the switch to the Apple Automotive Group today! At Apple Automotive, we Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.