I've had this problem too. Instead of checking for length, I check to see if the first item on the list is <> ''. If there is nothing in the first item, then I assume that it is an empty list. For the most part, the assumption is valid. for x in my_list: if x <> '': # do something... Hope that helps, Ron

ZClass "lines" type property is a "list" in Python.

If there are no values, it should render IMHO as an empty list in Python: []

But it renders as a list containing single item. Something like: [""]

Consequently, len(variable) is 1, whether there is one line or no lines.

I cannot use <dtml-if "_.len(variable)>0"> to see if there are values.

How can I discover if the list is empty without computationally expensive constructs?

-- Milos Prudek

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