TweetFollow Us on Twitter

Compiler Knows Rebuttal
Volume Number:8
Issue Number:6
Column Tag:Article Rebuttal

A Rebuttal to "The Computer Knows" Article

By Tim Swihart, Co-Author "Programming for System 7"

Just a couple of notes on the August issue (which arrived in my mailbox this weekend, so hopefully not too many other have yet mentioned some of this stuff).

• First off, great issue, v2.0 looks better with each new issue. Gar's column was great tounge-in-cheek fun!

• Secondly, a quick rebuttal to a portion of one of the articles in the August '92 issue. The problem is in John Love's “The Compiler Knows” article. The problem is on page 30, left hand column. John hard codes the menu ID for the item he appended to the help menu (#define myItem 3). That's very bad! Inside Mac, Volume VI, page 11-63 says, "In the future, Apple may choose to add other items to the Help menu. To determine the number of items in the Help menu, call the CountMItems function, which is described in the Menu Manager chapter of Volume 1."

In English, that translates to, "Don't hard code the ID of the item you append to the Help menu because the actual ID will change if Apple ever adds items to, or removes items from, the Help menu. Instead, let the toolbox tell you what ID was assigned to your item - since your item will always be at the end of the menu, CountMItems gives you the ID of the appended item."

This is a simple example of why existing applications break when new operating system features are added. In this case, doing it right is simple, so there's no reason to not do it right.

Also, John's code doesn't show what to do if your app added multiple items in the Help menu. How do you figure out which is which? "Programming for System 7" (Gary Little and Tim Swihart, Addison Wesley) shows how to handle it cleanly in Listing 8-5 (page 289). To paraphrase that approach (error checking and type declarations have been removed to simplify this explanation):

/* 1 */

HMGetHelpMenuHandle(&myHelpMenuHndl);
    bottomHelpItem = CountMItems(myHelpMenuHndl);
    secondHelpItem = bottomHelpItem - 1;
    thirdHelpItem = bottomHelpItem - 2;
    if (pickedItem == bottomHelpItem) {
        // code to do what you want when last item picked
    } else {
        if (pickedItem == secondHelpItem) {
 

         // code to execute when second to last item picked
        } else {
            if (pickedItem == thirdHelpItem) {
                // code for third to last item being picked
            }
        }
    }

One last point to make while on the subject of the Help menu. There are third-party inits available that remove the Help menu (freeing up that tiny bit of menubar space it occupies). But, some of them can have unexpected side effects on applications that assume they'll have a Help Menu since the Help Manager is present (which normally seems like a relatively valid assumption). Checking for errors returned by HMGetHelpMenuHandle() isn't enough. You'll also need to verify that the returned handle isn't nil if you want truly bulletproof code. Here's how I handle this in "BNDL Banger Pro":

/* 2 */

/* The following routine is responsible for appending  */
/* application-specific help items to the 'Help' menu. */
/* It's called from "Initialize()", just before        */       
/* "DrawMenuBar()" is called.                          */
void DoAddHMItems(void)
{
   MenuHandle  myHelpMenuHndl;
   OSErr   myErr;

   myErr = HMGetHelpMenuHandle(&myHelpMenuHndl);
   if ((!myErr) && (myHelpMenuHndl != nil)) {
 // check for nil in case some has removed the help menu 
     // (stop snickering,  I'm serious - there are such 
     // hacks readily available now )
   AppendMenu(myHelpMenuHndl,
   (ConstStr255Param)"\pBNDL Banger Pro Instructions");
   }
}

• Shifting gears considerably, I'd like to offer one last suggestion. Include the phone number for the MouseHole BBS in the MouseHole report section. [Right now, the Mousehole is on hiatus. Larry Nedry is the middle of a move to Texas. So for now, we can’t be of help here. - Ed.]

Thanks for listening.

 

Community Search:
MacTech Search:

Software Updates via MacUpdate

Safari Technology Preview 11.0 - The new...
Safari Technology Preview contains the most recent additions and improvements to WebKit and the latest advances in Safari web technologies. And once installed, you will receive notifications of... Read more
Geekbench 4.1.1 - Measure processor and...
Geekbench provides a comprehensive set of benchmarks engineered to quickly and accurately measure processor and memory performance. Designed to make benchmarks easy to run and easy to understand,... Read more
iMazing 2.3.3 - Complete iOS device mana...
iMazing (was DiskAid) is the ultimate iOS device manager with capabilities far beyond what iTunes offers. With iMazing and your iOS device (iPhone, iPad, or iPod), you can: Copy music to and from... Read more
TeamViewer 12.0.81279 - 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
Geekbench 4.1.1 - Measure processor and...
Geekbench provides a comprehensive set of benchmarks engineered to quickly and accurately measure processor and memory performance. Designed to make benchmarks easy to run and easy to understand,... Read more
iMazing 2.3.3 - Complete iOS device mana...
iMazing (was DiskAid) is the ultimate iOS device manager with capabilities far beyond what iTunes offers. With iMazing and your iOS device (iPhone, iPad, or iPod), you can: Copy music to and from... Read more
TeamViewer 12.0.81279 - 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
Safari Technology Preview 11.0 - The new...
Safari Technology Preview contains the most recent additions and improvements to WebKit and the latest advances in Safari web technologies. And once installed, you will receive notifications of... Read more
PDFpen 9.1 - $74.95
PDFpen allows users to easily edit PDF's. Add text, images and signatures. Fill out PDF forms. Merge or split PDF documents. Reorder and delete pages. Even correct text and edit graphics! Features... Read more
GraphicConverter 10.4.3 - $39.95
GraphicConverter is an all-purpose image-editing program that can import 200 different graphic-based formats, edit the image, and export it to any of 80 available file formats. The high-end editing... Read more

Latest Forum Discussions

See All

Galaxy of Pen & Paper has landed on...
If you enjoyed Knights of Pen & Paper and its sequel, you're in for a real treat, as Galaxy of Pen & Paper has officially launched on the App Store. Galaxy takes us far from the irreverent fantasy setting of Knights of Pen & Paper to a... | Read more »
Big changes are coming to Fire Emblem He...
Nintendo just revealed what players can expect from Fire Emblem Heroes in the coming weeks, with a good deal of fresh goodies arriving just in time for the game's six-month anniversary. The announcements arrived in a 15-minute FEH Channel stream... | Read more »
Aero Effect (Games)
Aero Effect 1.0.1 Device: iOS Universal Category: Games Price: $1.99, Version: 1.0.1 (iTunes) Description: Race an aerodynamic thingy through a maze of animated, geometric peril and plunge into a mysterious grid of pixels, all while... | Read more »
Linelight (Games)
Linelight 1.0 Device: iOS Universal Category: Games Price: $1.99, Version: 1.0 (iTunes) Description: Linelight is an elegant, minimalist puzzle game set in a universe of lines. Its puzzles will awake your mind as the music flows... | Read more »
Fighting Fantasy Legends (Games)
Fighting Fantasy Legends 1.0 Device: iOS Universal Category: Games Price: $4.99, Version: 1.0 (iTunes) Description: Create your own adventures in a dangerous land of monsters, treasures and traps. From renowned authors Steve Jackson... | Read more »
Knight Fever is a new take on the classi...
Knight Fever lands on the Google Play, and you won’t want to miss it if you’re a devoted RPG fan. Developed by indie creatives Buff Studios, the game looks like a retro RPG with some exciting new twists. | Read more »
Steam Panic (Games)
Steam Panic 1.0 Device: iOS Universal Category: Games Price: $3.99, Version: 1.0 (iTunes) Description: Steampunk puzzle in which you spin the playfield to put yourself back together. Dear Reader,Enclosed is a copy of my bizarre 1935... | Read more »
Time Crash (Games)
Time Crash 1.0 Device: iOS Universal Category: Games Price: $2.99, Version: 1.0 (iTunes) Description: Time is about to Crash! It’s up to you to save the city! Time Crash is a 3D first person runner which lets you play as a powerful... | Read more »
Galaxy of Pen & Paper (Games)
Galaxy of Pen & Paper 1.0.0 Device: iOS Universal Category: Games Price: $4.99, Version: 1.0.0 (iTunes) Description: *** NO IN-APP PURCHASES! ****** PREMIUM FOREVER *** THE ULTIMATE ROLE-PLAYING SIMULATION GOES TO SPACE! | Read more »
Niantic reveals more Pokémon GO legendar...
Oof. Pokémon GO Fest Chicago was pretty much a fiasco, huh? Niantic is feeling the heat from fans for their first big event that ultimately ended in failure. So much so that they've released a much longer apology that gives a full run down of... | Read more »

Price Scanner via MacPrices.net

27-inch 3.5GHz iMac on sale for $100 off MSRP...
Adorama has the new 27″ 3.5GHz iMac (MNEA2LL/A) on sale for $1899 including free shipping. Their price is $100 off MSRP. Adorama charges sales tax for purchases in NY & NJ only. Read more
Seven Cities, One Phone: OtterBox Sends iPhon...
Plenty of people have trekked around the world, but what about a globe-trotting iPhone? OtterBox is sending an iPhone around the world to capture the adventures of a diverse set of global ambassadors... Read more
L-Card Pro App May Spell End For Paper Busine...
OrangeTreeApps, LLC has announced the release of L-Card Pro 1.1, an update to their business app for iOS and Android devices that introduces eco-friendly, affordable, electronic business cards on the... Read more
Clearance previous generation iMacs, Apple re...
Apple has previous-generation Certified Refurbished 2015 21″ & 27″ iMacs available starting at $849. Apple’s one-year warranty is standard, and shipping is free. The following models are... Read more
27-inch 3.4GHz iMac on sale for $1699, save $...
MacMall has the new 2017 27″ 3.4GHz iMac (MNE92LL/A) in stock and on sale for $1699 including free shipping. Their price is $100 off MSRP. Read more
Photographer Explains Choosing Dell Laptop Ov...
Last week photographer and video blogger Manny Ortiz posted a video explaining the five most important reasons he settled on a Dell XPS 15 laptop instead of a MacBook Pro for his latest portable... Read more
Sale! 10-inch iPad Pros for $50 off MSRP, no...
B&H Photo has 64GB and 256GB 10.5″ iPad Pros in stock today and on sale for $50 off MSRP. Each iPad includes free shipping, and B&H charges sales tax in NY & NJ only: – 10.5″ 64GB iPad... Read more
WaterField Designs Upgrades TSA-friendly Zip...
San Francisco based designer and manufacturer Waterfield Designs has unveiled an upgraded and refined Zip Brief. Ideal for the minimalist professional, the ultra-slim Zip laptop bag actually holds a... Read more
USB 3.0 Promoter Group Announces USB 3.2 Upda...
The USB 3.0 Promoter Group has announced the pending release of the USB 3.2 specification, an incremental update that defines multi-lane operation for new USB 3.2 hosts and devices. USB Developer... Read more
Save on MacBook Pros with Apple Refurbished 2...
Apple recently dropped prices on Certified Refurbished 2016 15″ and 13″ MacBook Pros with models now as much as $590 off original MSRP. An Apple one-year warranty is included with each model, and... Read more

Jobs Board

*Apple* Solutions Consultant - Apple Inc. (U...
Job Summary As an Apple Solutions Consultant, you'll be the link between our future customers and our products. You'll showcase your entrepreneurial spirit as you Read more
Senior Software Engineer, *Apple* Online St...
Job Summary The Apple Online Store is looking for an experienced, self-driven, detail-oriented software engineer who can join our team to help build highly scalable Read more
Frameworks Engineering Manager, *Apple* Wat...
Frameworks Engineering Manager, Apple Watch Job Number: 41632321 Santa Clara Valley, California, United States Posted: Jun. 15, 2017 Weekly Hours: 40.00 Job Summary Read more
Senior Software Engineer, *Apple* Online St...
Changing the world is all in a day's work at Apple . If you love innovation, here's your chance to make a career of it. You'll work hard. But the job comes with more Read more
Frameworks Engineering Manager, *Apple* Wat...
Frameworks Engineering Manager, Apple Watch Job Number: 41632321 Santa Clara Valley, California, United States Posted: Jun. 15, 2017 Weekly Hours: 40.00 Job Summary Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.