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<scxml>

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The top-level wrapper element, which carries version information. The actual state machine consists of its children.

1. Attribute 'initial'

The id of the initial state(s) for the document. If not specified, the default initial state is the first child state in document order.

1.1. The id is not specified

<scxml name="Scxml" version="1.0" xmlns="http://www.w3.org/2005/07/scxml">
	<state id="Start">
		<onentry>
    		<log expr="Hello from 'start'"/>
  	  </onentry>
  	  <transition target="Work"/>
    </state>
    <state id="Work">
  	  <onentry>
  		  <log expr="Hello from 'work'"/>
  	  </onentry>
    </state>
</scxml>

Output:

[Log] "Hello from 'start'"
[Log] "Hello from 'work'"

1.2. The id is specified

  <scxml initial="Work" name="Scxml" version="1.0" xmlns="http://www.w3.org/2005/07/scxml">
	<state id="Start">
		<onentry>
			<log expr="Hello from 'start'"/>
		</onentry>
		<transition target="Work"/>
	</state>
	<state id="Work">
		<onentry>
			<log expr="Hello from 'work'"/>
		</onentry>
	</state>
</scxml>

Output:

Issue (WARNING) at //state[@id="Start"]: State with id 'Start' is unreachable
[Log] "Hello from 'work'"

2. Attribute 'datamodel'

The datamodel that this document requires. "null" denotes the Null datamodel, "ecmascript" the ECMAScript datamodel, and "xpath" the XPath datamodel or other platform-defined values.

<scxml datamodel="lua" name="Scxml" version="1.0" xmlns="http://www.w3.org/2005/07/scxml">
	<final id="End">
		<onentry>
			<log expr="string.format('Datamodel based on [%s]',_VERSION)"/>
		</onentry>
	</final>
</scxml>

Output:

[Log] "Datamodel based on [Lua 5.3]"

3. Attribute 'binding'

The data binding to use.

3.1. Early

When 'binding' is assigned the value "early" (the default), the SCXML Processor must create all data elements and assign their initial values at document initialization time.

<scxml datamodel="lua" initial="Step1" name="Scxml" version="1.0" xmlns="http://www.w3.org/2005/07/scxml">
	<state id="Step1">
		<onentry>
			<log expr="VarA" label="VarA"/>
		</onentry>
		<transition target="Step2"/>
	</state>
	<state id="Step2">
		<datamodel>
			<data expr="1" id="VarA"/>
		</datamodel>
	</state>
</scxml>

Output:

[Log] VarA: 1

3.2. Late

When 'binding' is assigned the value "late", the SCXML Processor must create the data elements at document initialization time, but must assign the specified initial value to a given data element only when the state that contains it is entered for the first time, before any markup.

<scxml binding="late" datamodel="lua" initial="Step1" name="Scxml" version="1.0" xmlns="http://www.w3.org/2005/07/scxml">
	<state id="Step1">
		<onentry>
			<log expr="VarA" label="VarA"/>
		</onentry>
		<transition target="Step2"/>
	</state>
	<state id="Step2">
		<datamodel>
			<data expr="1" id="VarA"/>
		</datamodel>
	</state>
</scxml>

Output:

[Log] VarA: nil

W3C IRP tests

1. Test 355

At system initialization time, if the 'initial' attribute is not present, the Processor MUST enter the first state in document order.

2. Test 576

At system initialization time, the SCXML Processor MUST enter the states specified by the 'initial' attribute, if it is present.

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