Andy Chase

While working my way through The Zope Book (2.6 edition), I finally got to the first practical example in the Using Basic Zope Objects chapter.

I created the example scripts as directed, diligently typed in the example templates and code (Copy paste works too, but I find when following programming tutorials that I memorize syntax more quickly if I type the examples out longhand), loaded the test form in the browser, and submitted it.

It crashed and burned with an error not remotely hinted at in the documentation. I checked and rechecked all of the code in all three of the application files, and everything was correct; parameters accounted for, no mismatched quotes, nothing.

It took me half an hour to figure out that I had misspelled the name of the Script (Python) object "calculateCompoundingInterest", which gets called by the interestRateDisplay template.

Instead of telling me that it couldn't find calculateCompoundingInterest, Zope was telling me that there was an error in it.

I'm sure there's an architectural reason for this behavior, and now that I know what the error caused by a missing object looks like I hopefully won't get stuck on this again, but it does seem peculiar.