[Zope] TypeError: cannot add type "Python Method" to string

[Ronald.Chichester@bakerbotts.com]

I am using a typical lookup routine in a python script to find information
about objects and return some of their properties.  The method works great
when you are making a comparison of strings.  E.g., the following code is
working just fine...

# Define a function to retrieve a particular class based on the element
number...
def get_class_by_title(objList, given_title):
  found    = 0
  ret_list = []
  # Run through the objects in the staff folder to see if there is a match
(with title)...
  for obj in objList:
    if found == 0:
      if given_title == obj.title:
        ret_list.append(obj.absolute_url)   # List element 0
        ret_list.append(obj.title)          # List element 1
        ret_list.append(obj.element_number) # List element 2
        ret_list.append(obj.instance_type)  # List element 3
        ret_list.append(obj.derived_from)   # List element 4
        ret_list.append(obj.figure_number)  # List element 5
        found = 1                           # Set flag on success...

  # Return indicative values if the desired object was not found...
  if found == 0:
    ret_list.append('Error')
    ret_list.append('Error')
    ret_list.append(-1)
    ret_list.append('Error')
    ret_list.append('Error')
    ret_list.append('Error')

  return ret_list

------------

... which is called by...

m = get_class_by_title(classList, j)


Unfortunately, the same, it seems, cannot be said when I make the comparison
using something other than a string.  For example...

# Define a function to retrieve a particular class association based on the
element number...
def get_class_association_by_element_number(objList, given_element_number):
  found    = 0
  ret_list = []
  # Run through the objects in the staff folder to see if there is a match
(with given_element_number)...
  try:
    for obj in objList:
      if found == 0:
        if given_element_number == obj.element_number:
          ret_list.append(obj.absolute_url)   # List element 0
          ret_list.append(obj.title)          # List element 1
          ret_list.append(obj.element_number) # List element 2
          ret_list.append(obj.instance_type)  # List element 3
          ret_list.append(obj.f_class)        # List element 4
          ret_list.append(obj.to_class)       # List element 5
          found = 1                           # Set flag on success...
  except:
    ret_list.append('Blew out of try block.')
    ret_list.append('Error')
    ret_list.append(-1)
    ret_list.append('Error')
    ret_list.append('Error')
    ret_list.append('Error')
    found = 1


  # Return indicative values if the desired object was not found...
  if found == 0:
    ret_list.append('Error')
    ret_list.append('Error')
    ret_list.append(-1)
    ret_list.append('Error')
    ret_list.append('Error')
    ret_list.append('Error')

  return ret_list

... consistently returns an error when called by...

n = get_class_association_by_element_number(classAssociationList,
string.atoi(j))

where j is a string element that is stored in a lines property of the object
in question.

When this code is executed, I get a TypeError:  cannot add type "Python
Method" to string

Does anyone know what the problem is?

Note, I've done some diagnostics and simply had the method return the input
value (given_element_number) and it does so properly.  

Here is the rest of the diagnostic information...

Traceback (innermost last):
  File /usr/local/zope/2-4-3/lib/python/ZPublisher/Publish.py, line 223, in
publish_module
  File /usr/local/zope/2-4-3/lib/python/ZPublisher/Publish.py, line 187, in
publish
  File /usr/local/zope/2-4-3/lib/python/Zope/__init__.py, line 226, in
zpublisher_exception_hook
    (Object: 066543_0103)
  File /usr/local/zope/2-4-3/lib/python/ZPublisher/Publish.py, line 171, in
publish
  File /usr/local/zope/2-4-3/lib/python/ZPublisher/mapply.py, line 160, in
mapply
    (Object: get_text)
  File /usr/local/zope/2-4-3/lib/python/ZPublisher/Publish.py, line 112, in
call_object
    (Object: get_text)
  File /usr/local/zope/2-4-3/lib/python/Shared/DC/Scripts/Bindings.py, line
324, in __call__
    (Object: get_text)
  File /usr/local/zope/2-4-3/lib/python/Shared/DC/Scripts/Bindings.py, line
354, in _bindAndExec
    (Object: get_text)
  File
/usr/local/zope/2-4-3/lib/python/Products/PythonScripts/PythonScript.py,
line 363, in _exec
    (Object: get_text)
    (Info: ({'script': <PythonScript instance at 8ae0a88>, 'context':
<Folder instance at 8cd9a20>, 'container': <Folder instance at 8b17d48>,
'namespace': <TemplateDict object at 0x87eb248>, 'traverse_subpath': []},
('0',), {}, None))
  File Script (Python), line 264, in get_text
TypeError: (see above)


This is a really strange error.  Can anyone give me a hint as to what the
problem is?

Thanks in advance,

Ron