Summary

The Tau expressions used in constructors can actually also be used stand-alone. In fact, the distribution contains an interpreter for Tau expressions which will cover in some detail later. One of the niceties of Tau expressions is that they play well together with TMQL path, the path expression query language. Also more about this later.

Somewhat connected with merging is the concept of transactions. In some cases you would want to apply all the techniques you are used from relational databases to enforce a certain degree of time consistency in your map(s). Also here the interface will offer some support to create, commit or rollback changes.

Another major feature which warrants its own coverage are map spheres. Map spheres are a topic map backend; here you can store your maps for later reference. At the moment there are several implementations of such backends: a persistent one using Berkeley DB files or a non-persistent one using only memory. There is even a protocol which allows to communicate with a remote backend. If you have a small cluster you may be interested to hear that these backends can be integrated into one logic backend.

Good fun is writing drivers. You have a resource you would like to bring into the TM realm? Simply write an ontology and hack away a driver. At the moment pretty everything there is footwork, unfortunately, so some support packages have to be developed first.