The LSPS Expression Language is a language used in models of the Living Systems® Process Suite to define element properties, definition implementations, assignments, etc. As such, it provides support for object-oriented and functional programming.
Note that it is not a full-fledged programming language and it is not possible to define models exclusively in the LSPS Expression Language; the language is adapted to support your modeling efforts.
For example, you design a BPMN process with a Log task, you define the log message as an expression or expression block that results in a String in the Log property:
"Process " + processID + " started."
This expression uses String literals "Process " and " started", and the variable processID. On runtime, the system fetches the value of processID and concatenates the strings.
However, you cannot design the process flow with the Start Event and Log task in the Expression Language; For this purpose, you will use constructs of the GO-BPMN Modelling Language.