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Contents Overview Examples Editor Forum

<state>

Video version

Holds the representation of a state.

state - atomic

<scxml name="Scxml" version="1.0" xmlns="http://www.w3.org/2005/07/scxml">
	<state id="StateAtomic"/>
</scxml>

Attribute 'id'

The identifier for this state.

Attribute 'initial'

The id of the default initial state (or states) for this state.

Example: 'State1' is specified as initial

state - initial 1

<scxml name="Scxml" version="1.0" xmlns="http://www.w3.org/2005/07/scxml">
	<state id="Work" initial="State1">
		<state id="State1">
			<onentry>
				<log expr="Hello!" label="State 1"/>
			</onentry>
			<transition event="Step" target="State2"/>
		</state>
		<state id="State2">
			<onentry>
				<log expr="Hello!" label="State 2"/>
			</onentry>
			<transition event="Step" target="State3"/>
		</state>
		<state id="State3">
			<onentry>
				<log expr="Hello!" label="State 3"/>
			</onentry>
			<transition event="Step" target="State1"/>
		</state>
	</state>
</scxml>

Output:

[Log] State 1: "Hello!"

Example: 'State3' is specified as initial

state - initial 2

<scxml name="Scxml" version="1.0" xmlns="http://www.w3.org/2005/07/scxml">
	<state id="Work" initial="State3">
		<state id="State1">
			<onentry>
				<log expr="Hello!" label="State 1"/>
			</onentry>
			<transition event="Step" target="State2"/>
		</state>
		<state id="State2">
			<onentry>
				<log expr="Hello!" label="State 2"/>
			</onentry>
			<transition event="Step" target="State3"/>
		</state>
		<state id="State3">
			<onentry>
				<log expr="Hello!" label="State 3"/>
			</onentry>
			<transition event="Step" target="State1"/>
		</state>
	</state>
</scxml>

Warning!

1. MUST NOT be specified in conjunction with the <initial> element. state - initial - warning 1

<scxml name="Scxml" version="1.0" xmlns="http://www.w3.org/2005/07/scxml">
	<state id="Work" initial="State1">
		<state id="State1">
			<onentry>
				<log expr="Hello!" label="State 1"/>
			</onentry>
			<transition event="Step" target="State2"/>
		</state>
		<state id="State2">
			<onentry>
				<log expr="Hello!" label="State 2"/>
			</onentry>
		</state>
		<initial>
			<transition target="State1"/>
		</initial>
	</state>
</scxml>

Output:

Issue (WARNING) at //state[@id="Work"]: State with initial attribute cannot have <initial> child

2. MUST NOT occur in atomic states.

<scxml name="Scxml" version="1.0" xmlns="http://www.w3.org/2005/07/scxml">
	<state id="StateAtomic" initial="StateXXX"/>
</scxml>

Output:

Issue (FATAL) at //state[@id="StateAtomic"]: Initial attribute has invalid target state with id 'StateXXX'

Atomic state

Has no <state>, <parallel> or <final> children.

state - atomic

Compound state

Has <state>, <parallel>, or <final> children (or a combination of these).

state - compaund - atomic

<scxml name="Scxml" version="1.0" xmlns="http://www.w3.org/2005/07/scxml">
	<state id="StateCompaund">
		<state id="StateAtomic"/>
	</state>
</scxml>

Default initial state

Specified by the 'initial' attribute or <initial> element, if either is present. Otherwise it is the state's first child state in document order.

Example 1

state - initial - default

<scxml name="Scxml" version="1.0" xmlns="http://www.w3.org/2005/07/scxml">
	<state id="Work" initial="State2">
		<state id="State1">
			<transition event="Step" target="State2"/>
		</state>
		<state id="State2">
			<onentry>
				<log expr="I am initial!" label="State 1"/>
			</onentry>
			<transition event="Step" target="State1"/>
		</state>
	</state>
</scxml>

Example 2

state - initial - default - document order

<scxml name="Scxml" version="1.0" xmlns="http://www.w3.org/2005/07/scxml">
	<state id="Work">
		<state id="State1">
			<onentry>
				<log expr="I am initial!" label="State 1"/>
			</onentry>
			<transition event="Step" target="State2"/>
		</state>
		<state id="State2">
			<transition event="Step" target="State1"/>
		</state>
	</state>
</scxml>

W3C IRP tests

Test 364

Definition: The default initial state(s) of a compound state are those specified by the 'initial' attribute or initial element, if either is present. Otherwise it is the state's first child state in document order. If a compound state is entered either as an initial state or as the target of a transition (i.e. and no descendent of it is specified), then the SCXML Processor MUST enter the default initial state(s) after it enters the parent state.

test364

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