example: overlay chain positive space
Let's extend the simple example to add an intermediate template, so we
therefore have an overlay chain conisting of 3 templates, namely
overlay_chain_pos.html over overlay_mid.html
over the unmodified base.html (from simple example).
The templates
overlay_mid.html
$overlay{base.html}
-ve space (overlay_mid.html)
$begin{footer}<span>overlay_mid footer</span>$end{footer}
-ve space (overlay_mid.html)
- an intermediate positive overlay on base.html
- the -ve space from base.html is imposed
- overrides one +ve block, #footer
overlay_chain_pos.html
$overlay{overlay_mid.html}
<html>
<head><title>template = ${title}</title></head>
<body> <span> -ve space (overlay_chain_pos.html) </span>
$begin{content} overlay_chain_pos ${parametrized} content $end{content}
<div class="header">$evoque{#header}</div>
<div class="content">$evoque{#content}</div>
<div class="footer">$evoque{#footer}</div>
</body>
</html>
- overrides the positive space of overlay_mid.html, redefining #content
- when evoque'd directly, this template is rendered with:
- the -ve space from below
- own #content
- the #header and #footer from below
Output
Rendering the overlay:
name = "overlay_chain_pos.html"
domain.get_template(name).evoque(title=name, parametrized="HAPPY")
Will give the following output (note negative space used is that from base.html):
<html>
<head><title>template = overlay_chain_pos.html</title></head>
<body> <span> -ve space (base.html) </span>
<table class="layout">
<tr><td>+ve space: base header </td></tr>
<tr><td>overlay_chain_pos HAPPY content </td></tr>
<tr><td><span>overlay_mid footer</span></td></tr>
</table>
</body>
</html>