[Zope] Does Zope use dynamic scoping?

15 May 1999

      I'm new to this, but I've got quite far and now I'm stuck - help!

This is with Zope-1.11.0pr1 under Linux.

As an exercise, I'm trying to write a Slashdot-esque threaded comment
system using PostgreSQL and ZPyGreSQL, and I wonder if my assumptions
about scoping are biting me.

Comments have an Object Identifier, "oid".  I have an SQL method
"allcomments" that looks up all comments, and defines "oid" among
other variables (eg "subject").  "responses" looks up all the comments
that are responses to "oid".

allcomments looks like this:

  select *, oid
  from comments

and repliesto like this:

  select *,oid
  from comments
  <!--#sqlgroup required where-->
    <!--#sqltest oid column=reference type=int optional-->
  <!--#/sqlgroup-->

This code works fine:

<!--#if repliesto-->
  <ul>
    <!--#in repliesto-->
    <li><!--#var subject-->
    <!--#/in-->
  </ul>
<!--#/if-->

So why is it that this code works fine:

  <ul>
    <li>Before
    <!--#in allcomments-->
      <li><!--#var subject-->
      <ul>
        <li>Before: <!--#var subject-->
        <!--#var oid-->
        <!--#in allcomments-->
          <li><!--#var subject-->
        <!--#/in-->
        <li>After: <!--#var subject-->
      </ul>
    <!--#/in-->
    <li>After
  </ul>

and does what you expect (in particular, the subject doesn't change
across the inner allcomments), but if I replace the inner
"allcomments" with "repliesto", I get this:

  Zope Error

    Zope has encountered an error while publishing this resource. 

    Error Type: Bad Request
    Error Value: ['oid']

This is frustrating my attempts to use recursion to build threading
trees, it's late and I've written too many test scripts.  Help much
appreciated!
-- 
  __
\/ o\ paul@hedonism.demon.co.uk  http://www.hedonism.demon.co.uk/paul/ \ /
/\__/ Paul Crowley            Upgrade your legacy NT machines to Linux /~\