ZPT Sharp Zen HTML views

Defining and using METAL macros

metal:define-macro

Attribute syntax

metal:define-macro="MACRONAME"

Remarks

Indicates that the current element and all of its child elements form a macro with the given name (MACRONAME). Alone this attribute does nothing, but the macro may now be referenced by either use-macro or metal:extend-macro attributes.

metal:use-macro

Attribute syntax

metal:use-macro="EXPRESSION"

Remarks

Creates a copy of the markup tree represented by the macro EXPRESSION ("the macro"). The macro is extended and slots are filled if appropriate. Then the current element (the element decorated use-macro) and its children/content is replaced with the referenced macro (the corresponding element decorated with define-macro).

Macro definition and usage example

The following simple example shows a common page header macro:

<!-- Macro definition -->
<body>
  <header metal:define-macro="page_header">
    <a href="homepage_url">Boyd's toast</a>
    <p class="strapline">Our toast really <em>pops!</em></p>
  </header>
</body>

<!-- Macro usage -->
<body>
  <header metal:use-macro="page_header">Uses the common header</header>
  <section class="main_content">
    <p>Here's the main page content</p>
  </section>
</body>

<!-- How this renders -->
<body>
  <header>
    <a href="homepage_url">Boyd's toast</a>
    <p class="strapline">Our toast really <em>pops!</em></p>
  </header>
  <section class="main_content">
    <p>Here's the main page content</p>
  </section>
</body>