METAL Overview

  The *Macro Expansion Template Attribute Language* (METAL) standard
  is a facility for HTML/XML macro preprocessing. It can be used in
  conjunction with or independently of "TAL":tal.stx and
  "TALES":tales.stx.

  Macros provide a way to define a chunk of presentation in one
  template, and share it in others, so that changes to the macro are
  immediately reflected in all of the places that share it.
  Additionally, macros are always fully expanded, even in a template's
  source text, so that the template appears very similar to its final
  rendering.

  METAL Namespace

    The METAL namespace URI and recommended alias are currently
    defined as::

      xmlns:metal="http://xml.zope.org/namespaces/metal"

    Just like the TAL namespace URI, this URI is not attached to a web
    page; it's just a unique identifier.

    Zope does not require an XML namespace declaration when creating
    templates with a content-type of 'text/html'. However, it does
    require an XML namespace declaration for all other content-types.

  METAL Statements 

    METAL defines a number of statements:

    * "metal:define-macro":metal-define-macro.stx - Define a macro.

    * "metal:use-macro":metal-use-macro.stx - Use a macro.

    * "metal:define-slot":metal-define-slot.stx - Define a macro
    customization point.

    * "metal:fill-slot":metal-fill-slot.stx - Customize a macro.

    Although METAL does not define the syntax of expression
    non-terminals, leaving that up to the implementation, a canonical
    expression syntax for use in METAL arguments is described in
    "TALES Specification":tales.stx.

  See Also

    "TAL Overview":tal.stx

    "TALES Overview":tales.stx

    "metal:define-macro":metal-define-macro.stx

    "metal:use-macro":metal-use-macro.stx

    "metal:define-slot":metal-define-slot.stx

    "metal:fill-slot":metal-fill-slot.stx