[Zope] What's up with calling DTML methods with arguments?

[John Morton]

John Morton writes:
 > Scenario: 
 > 
 > So in my password change report I want to do something like this:
 > 
 > (name and new_password arrive from the request, pwd_format is an
 > acquired default)
 > 
 > <dtml-call "sql_change_password(
 >  user_id=sql_get_user_id(name=name),
 >  password=encodePassword(password=new_password),
 >  pwd_format=pwd_format
 > )">
 

Of course this won't work because user_id ends up being a list
reference or something, so I tried this:

 <dtml-let name="'jwm'" old_password="'clear'" new_password="'foobar'">
   <dtml-let password=new_password>
    <dtml-let enc_pass="encodePassword">
     <dtml-in "sql_get_user_id(name=name)">
       <dtml-call "sql_change_password(user_id=id,password=enc_pass,pwd_format=pwd_format)">
     </dtml-in>
    </dtml-let>
   </dtml-let> 
 </dtml-let>

...which also doesn't work, resulting in more complaints about
infinite recursion. But this does:

 <dtml-let name="'jwm'" old_password="'clear'" new_password="'foobar'">
   <dtml-let password=new_password>
    <dtml-let enc_pass="encodePassword">
     <dtml-in "sql_get_user_id(name=name)">
       <dtml-if enc_pass>
       <dtml-call "sql_change_password(user_id=id,password=enc_pass,pwd_format=pwd_format)">
       </dtml-if>
     </dtml-in>
    </dtml-let>
   </dtml-let> 
 </dtml-let>

It looks like a side effect of the caching properties of <dtml-if ...> 
is that encodePassword gets evaluated at the 'if'. Of course, I
expected it would get evaluated at the <dtml-let> tag, but it appears
that in the first piece of code it gets evalutate in
sql_change_password somehow, so that it's trying to get a value for
password by calling encodePassword which needs a property called
password, so it tries to get a value for password...

Is that what's happening? Should it be?

John.