I have this code in my spider basic.py file:

if l.add_xpath('price', '//*[@id="price"]/text()',MapCompose(lambda i: i.replace(',', ''), float),re = '[,.0-9]'):l.add_value('available', 1)
else:l.add_value('price', 0)l.add_value('available', 0)

The expected result is available = 1 when there is a price found, but what I get is 0 and I don't understand why!

Any ideas?

Just in case someone ran into the same situation:

The answer is that add_xpath does not return anything, and in order to check whether there is an element found or not, get_xpath should be used instead (see here).