Project Vision


Presentation Designers like to work with sophisticated visually oriented web page tools where they can sculpt presentation in the context of the prototypical content. DTML uses its own non-HTML markup which is counter to the way most web page editors work. Through the extensive use of DTML, content is dynamically generated and prototypical proxies (for said content) is not available to the designer. In addtion, content, presentation and logic are all blended into one place and each respective party is expected to keep their hands off of the other’s domain.

Proposed Solution

Adopt a consistent, XML compliant, markup language as a target, embed all logic in namespaced attributes (where they are ignored by the web page tools) and provide a means to supply prototypical content to give the presentation designer a sense of context.

The solution shall have the following characteristics:

  • Everything is explicit. There are no implicit contexts or magic side effects.
  • Separates Presentation from Content and Business Logic.
  • Work with plain old HTML as well as XML.
  • XML compliant.
  • Allows example content in PageTemplates to allow designers to see/edit their work in context (idea courtesy of HiperDOM).
  • Macro based template facility. You can create paramaterized chunks of Presentation that can be applied as macros in pages.
  • Many of these ideas are universal. Things that are not Zope specific shouldn’t be made Zope specific.

Risk Factors

See Risk Factors


This markup language will replace DTML for most general functionality and will be accompanied by tools that will help the Presentation Designer’s tools import and export pages to and from Zope.

This markup language will not be Zope specific in design, but may be so in implementation.

See the Frequently Asked Questions for additional information.


  1. The Template Attribute Language (TAL Reference)
  2. The Template Attribute Language Expression Syntax (TALES Reference)
  3. The Template Attribute Language Macros (METAL Reference)
  4. PageTemplates


jeske (Apr 3, 2002 6:05 pm; Comment #2) –
I recommend you take a look at Clearsilver is an extremely fast template system which separates presentation from application logic. It is based on the template system we used internally for and which is still used for Yahoo Groups.