[Zope] Zope 2.4 / DTML problem: With looping over two sets

Tue, 21 Aug 2001 00:14:41 -0000

Hi there,

maybe a newbie question...

I try to dtml a cursor-object of an own python-database, swigged from 
a C-project (Gigabase).

Actual the cursor-class has __getitem__ with throwing of IndexError. 
BUT: it has no real random access via index-number!

its behavior is like this (a little bit simplifying):

...
cursor.first()           #get first position
cursor[anyNumber]        #if number == 0: return cursor.get()
                         #else: cursor.next().get()
                         #if next() has no result or number > len
(cursor), or len(cursor)==0 the exception is thrown and a loop will 
stop
...

so, a simple code-snippet

cursor.first()
for c in cursor:
   for r in c.rows:
      ...process something...

works perfect for me!

Now following DTML-code makes a unaccepted error (I've had very few 
accepted errors :-))... obviously the render-code access the 
cursor.__getitem__ method in second loop (-->c_item) again with 
static index-number!
Bad for my stupid implementation, and not pythonlike where a loop in 
a loop works with an own loop-variable.

I doesn't expect a continous __getitem__ with 'same' index-number, 
and I don't know how to workaround it on C-language-site

first steps to program this page (and this is only the beginning!) 
the "classic" way, leads me directly to your mailinggroup and the 
urgent wink for help!!! I like the DTML way, and I want to use it!

Anybody a tip or patch, workaround, whatever???

thanks a lot
Peter
(=PA=)
:

t = DocumentTemplate.HTML("""
  <html><head><title><dtml-var 
expr="cursor.entityName"></title></head>
  <body>
  <dtml-if expr="cursor.__len__()">
      <p>Die Suche ergab <dtml-var expr="cursor.__len__()"> Treffer!
</p>
      <table>
          <tr>
          <dtml-in expr="cursor.rowNames">  <----- OUTER LOOP
              <th><dtml-var sequence-item></th>
          </dtml-in>
          <tr>
          <dtml-in cursor prefix="c">       <------ INNER LOOP
              <tr>
              <dtml-in expr="cursor.rowNames" prefix="r">
                  <td><dtml-var expr="c_item.__getattr__
(r_item)"></td> <---- c_item access my cursor again with __getitem__! 
instead of a loop-variable
              </dtml-in>
              </tr>
          </dtml-in>
      </table>

  <dtml-else>
      <p>Die Suche ergab keine Treffer!</p>
  </dtml-if>
  <p>Generated by Miracle</p>
  </body>
  </html>
  """)