e main use for parameterized types are libraries implementing abstract
data types
(<a href="http://www.freelists.org/post/luajit/ffi-type-of-pointer-to,8"><span class="ext">&raquo;</span>&nbsp;example</a>),
similar to what can be achieved with C++ template metaprogramming.
Another use case are derived types of anonymous structs, which avoids
pollution of the global struct namespace.
</p>
<p>
Please note that parameterized types are a nice tool and indispensable
for certain use cases. But you'll want to use 