[Zope] Squishdot Error on Zope 2.6.0

[Jens Vagelpohl]

> Jens Vagelpohl wrote:
>> it's just that making assumptions about what the environment looks 
>> like is never a good idea.
>
> If you made no assumptions, you'd write no code.

it is, especially in this case, easy to guard against changing 
environments.


>> it is really easy on the other hand to add code that determines what 
>> indexes are really available or to surround the deletion code with 
>> try/except statements. it'll save you support questions in the long 
>> run.
>
> ...and if you write a try/except for every possible name or piece of 
> code that may change in the future, you'll end up with an infinitely 
> large piece of code.

if you don't like try/except you can use the well-known catalog APIs 
for determining the IDs of metadata columns and indices.


> Sorry, your logic is flawed. This is just 'one of those things' that 
> happens when people change code that other code relies on. Sadly, 
> ZCatalog has been particularly prone to that over the years...

you're correct, ZCatalog has seen many changes. but instead of giving 
up and hardcoding an expected environment just a couple more lines of 
code can go a long way towards ameliorating the impact of those changes.

jens