Jenner is a Web page templating system with a twist: it runs completely within a Web browser. Templates are just normal Web pages with special syntax inside text nodes, attributes, or comments. Unlike other in-browser templating systems, Jenner does not require overloading of "class" attributes or invalid HTML; all Jenner templates are valid Web pages and the template expressions flow in a very natural way. Having the template engine in the Web browser instead of on the server takes a lot of load off of the server, and makes for a clean separation of presentation and content. Jenner is very powerful: it has the full power of the Esel expression language at its disposal. Templates can be rendered from JSON data, and can be re-rendered without a browser-to-server round trip.
PHPTAL is a fast, safe, XML-based template engine for XHTML and HTML5. It implements Zope's Template Attribute Language, which has clean, concise syntax that is compatible with XML tools (no custom ugly tags), and template source files can even be previewed in Web browsers or opened in WYSIWYG editors. Templates are compiled to PHP and cached, giving great performance and taking advantage of PHP accelerators. PHPTAL by default ensures well-formed output and escapes XML-unsafe characters everywhere, which means that your pages can be completely safe against HTML-injection (XSS) without great effort. It features fine-grained caching of output, pre- and post- filters, internationalization via gettext or custom backend, creation of custom template attributes and expressions, and templates loaded from non-standard sources (e.g. databases). It supports UTF-8 well, is easy to integrate and redistribute with PHP frameworks and applications, and has an object-oriented design and a comprehensive unit test suite.
Succinct is a minimal templating engine designed for concurrency and efficiency. It has an especially abstract data model, allowing you to back your templates by fetching template data on-demand, during render-time, according to your own complex synchronization protocols. It comes with lots of tools to help you make your data "templatable."
terp is a modular template engine that integrates tightly into ANT and provides a portable C++ compiler task (aCC, g++, icc, msvc++, SUN CC, xlC) on many platforms and processor architectures, a collection iterator task, a full-featured expression language with host introspection, formatters, selectors, and transformers for expressions, and much more. It can be embedded into Ant, used as a stand-alone or embedded templating engine, or used as a batch or interactive expression evaluator. It is extremely flexible and can be extended with your own types, operators can be overloaded, and properties and methods can be added to types.