Keeping good on a promise

In a pervious post, I said that I'd purchase the products from Potion Factory even though I currently have no use for them because Andy Kim's open source PotionStore is a perfect solution for my own store. Well, I kept forgetting about this and finally got around to making the purchase this morning. Thanks again, Andy, for the store; not only is it working beautifully, it has also gotten me interested in Ruby on Rails.

Exceptions and error handling

One of the things users hate to see are bugs in programs, so there are many techniques for attempting to catch them before a user sees them. One that is routinely used is exception handling. However, some developers like to use exception handling instead of preventing the issue or gracefully handling it. For example, I was working on code to present errors (in a worst case scenario) to users and trapped the error handling. As I did this, I kept noticing strange exceptions being thrown when my app started. Turns out that Apple uses exceptions (which are benign) in Core Data for its parsing of XML. Personally I don't think this is a great way of handling things, but who am I to judge?

On the same topic, I had a rash of users complain that they lost data in my apps. I was very perplexed as I'd never seen this. I took a look at the code where I save out the data and noticed that I had put the entire save routine along with some other routines in an exception block with the save being at the end. This meant that if there was a problem with the first chunk of code, the data would never get saved. While I still have no idea what would cause the first chunk of code to fail, I pulled the save out of the exception handling and have yet to receive a problem report (knock on wood).

So the moral of the story is to carefully watch how exceptions are used and don't go overboard with exception handling.

Recovering my sales tax

After several email exchanges, I've been refunded the $6.93 and $3.10 from ASI Order and VMWare, respectively for the sales tax they collected on my completely electronic downloads (the first for the marathon pictures I ordered and the second for a copy of VMWare Fusion). This is a small victory for me, but I feel that these companies need to get with the 20th century and look at the tax laws for electronic commerce. ASI Orders appears to still be charging sales tax on their website, so I suspect they refunded my money on the sales tax to get me to be quiet.

DocumentWallet on MacUpdate Promo

Tomorrow, Tuesday, July 3, DocumentWallet will be on MacUpdate Promo for a special price. This is a one day only promotion and may not be repeated in the future, so hurry. If you've already a ReceiptWallet user, you'll get a better price by going to the coupon form on our website to have a 50% off (regular price) coupon sent to you.