W3C State Chart XML (SCXML)¶

fsmc provides bidirectional parsing and code generation for the W3C State Chart XML (SCXML) standard.

1. Supported SCXML Elements¶

<scxml>: Root statechart with initial state attribute.
<state>: Atomic and composite states with nested states.
<initial>: Explicit initial transition block.
<transition>: Transitions with event, cond (guard predicate), and target attributes.
<onentry> and <onexit>: Lifecycle action blocks.
<history>: Shallow and deep history elements (type="shallow|deep").
<final>: Termination states.

2. Example SCXML Statechart¶

<?xml version="1.0" encoding="UTF-8"?>
<scxml xmlns="http://www.w3.org/2005/07/scxml" version="1.0" initial="Standby">
    <state id="Standby">
        <transition event="StartCmd" target="Active"/>
    </state>

    <state id="Active" initial="Operational">
        <state id="Operational">
            <transition event="PauseCmd" target="Paused"/>
        </state>
        <state id="Paused">
            <transition event="ResumeCmd" target="Operational"/>
        </state>
        <transition event="StopCmd" target="Standby"/>
    </state>
</scxml>

Compile with:

fsmc -i statechart.scxml -o statechart_fsm.hpp --std 20