John Grey wrote at 2004-1-26 13:13 +0000:

... I am now trying to create a simple product which clones a tinytableplus. I have set it up similarly to the zoo exhibit example in the Zope book.

apart from the stuff to redirect back, the add script includes only

newgrid=context.manage_clone(container[source],id)

where 'source' is a parameter passed from an 'add form' to determine which of several tinytables to use (these are in the product folder).

This works if I try to add the product to the product folder itself by viewing and submitting the add form that calls the script but when I try to use the normal add product drop down list I get this error:

Error Type: AttributeError Error Value: __getitem__

Everything works OK if I substitute the actual name of a tinytable (preceded by .) like this.

newgrid=context.manage_clone(container.grid,id)

You should have used the "standard" way for computed attribute access (--> "getattr"). Instead, you decided to use a special case: the subscription syntax ("obj[id]"). This is only provided by "Folder" instances. However, when you use "dest/manage_addProduct/ProductName/constructor", then the "container" of "constructor" is a product dispatcher instance. This is not a "Folder". "getattr" would have worked through acquisition. As a general rule: go for the standard way; use a non-standard one only when you know what you do. You can forget about computed attribute access through subscription syntax. -- Dieter