A simple bulletin system

This is a crude bulletin system written in Meso. The Board class stores messages in an array, while the Client class always sends it the same message. Nonetheless, one can easily modifies Board to use a persistent storage, and add a nice interactive GUI to Client for sending different messages. Our attention is on the relationship between these classes. While this version does not use any network, we will latter develop a distributed version based on the same architecture.

All UTLs in this example, such as meso:service.IBulletin or meso:app.Client, have meso: as their protocol — or more correctly, as their type scheme. Data types of the Meso scheme is accessible only within the local Meso runtime. They cannot be located from the network, and therefore their UTLs do not have a network address portion.

meso  :  service.IBulletin
^^^^     ^^^^^^^^^^^^^^^^^
The meso type scheme        Local name