I am working on a rapid html prototyping framework. This would allow me (as an interaction designer) to create html prototypes fast.

I have been looking in templating plugins to help with building the templates or filling them with content. For example {{ lorem_ipsum }} would be replaced with a few paragraphs of random text. This is easy to do with several plugins.

However it would be great to be able to add a bit more flexibility by using functions like {{ loremWords(100) }} which would add 100 random words which are different for each replaced item. Or something similar to add a menu or other snippets.

Any ideas if there are any plugins that can handle this or how to create this myself? 

It is probably not too difficult but so far I have not gotten it working yet. And the plugins I have found are either too complex, requires script tags or can't handle functions.

thanks!