DSL:-AshStateMachine.md

DSL: AshStateMachine

Provides tools for defining and working with resource-backed state machines.

state_machine

Nested DSLs

• transitions
  • transition

Options

Name	Type	Default	Docs
initial_states{: #state_machine-initial_states .spark-required}	list(atom)		The allowed starting states of this state machine.
deprecated_states{: #state_machine-deprecated_states }	list(atom)	[]	A list of states that have been deprecated but are still valid. These will still be in the possible list of states, but :* will not include them.
extra_states{: #state_machine-extra_states }	list(atom)	[]	A list of states that may be used by transitions to/from :*. See the docs on wildcards for more.
state_attribute{: #state_machine-state_attribute }	atom	:state	The attribute to store the state in.
default_initial_state{: #state_machine-default_initial_state }	atom		The default initial state

state_machine.transitions

Wildcards

Use :* to represent "any action" when used in place of an action, or "any state" when used in place of a state.

For example:

transition :*, from: :*, to: :*

The full list of states is derived at compile time from the transitions. Use the extra_states to express that certain types should be included in that list even though no transitions go to/from that state explicitly. This is necessary for cases where there are states that use :* and no transition explicitly leads to that transition.

Nested DSLs

• transition

state_machine.transitions.transition

transition action

Arguments

Name	Type	Default	Docs
action{: #state_machine-transitions-transition-action .spark-required}	atom		The corresponding action that is invoked for the transition. Use :* to allow any update action to perform this transition.

Options

Name	Type	Default	Docs
from{: #state_machine-transitions-transition-from .spark-required}	list(atom) | atom		The states in which this action may be called. If not specified, then any state is accepted. Use :* to refer to all states.
to{: #state_machine-transitions-transition-to .spark-required}	list(atom) | atom		The states that this action may move to. If not specified, then any state is accepted. Use :* to refer to all states.

Introspection

Target: AshStateMachine.Transition

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