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XSM (executable state model) parser documentation

This wiki explains how a Shlaer-Mellor Executable UML state model is defined in an xsm text file.

A Shlaer-Mellor state model is either a lifecycle, which describes the behavior of every instance of a class, or an assigner, which arbitrates competition for instances of a class across a relationship. One xsm file defines exactly one of these. See Lifecycle or Assigner if that distinction is new to you.

The examples throughout this wiki are drawn from the Elevator Management domain, primarily the Door lifecycle with the R53 assigner standing in wherever an assigner is the better illustration.

Despite best efforts to keep this documentation up to date, you may encounter discrepancies with the grammar file which is the real ground truth.