Fascinated to hear of Enlive. I've been thinking about this concept for a few years and have hacked together something in PHP that shares some principles: templates are pure HTML, and you "fill" them by addressing content to a specific node in the document using CSS or XPath.
$t = new Template('yourfile.html');
$t->fill('#nav',$someMarkup);
$t->fill('#header',$otherMarkup);
I also experimented with throwing together some provisions for separating the content out into a "stylesheet" of sorts... well, "stylesheet" is the wrong word. I'm calling them content-addressing sheets (the project is called CAST, for content-addressed-style-templating). A CAS looks like you might expect:
.col #foot {
content: 'foot';
}
#content {
content: file_get_contents('pangolin.txt');
}
The values of content are assumed to be PHP expressions. There's some provision for setting up PHP that applies across selectors, too.
Take a run of the cssfill.php script that's in the tarball (best invocation is probably ./cssfill.php pangolin.cas pangolin.html, you might have to change the path to your php interpreter inside cssfill.php), take a look at the output, compare with the input files.
If this post generates any enthusiasm for the idea in you, feel free to let me know. I've been wondering whether this was a crazy idea or whether it has a place, if it does, I'd be happy to turn it into a thoughtfully released open source project as opposed to a tarball randomly tossed onto the internet.