consul/ui/packages/consul-ui/app/components/state-machine

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class: ember
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# StateMachine

```hbs
<StateMachine
  @chart={{xstateStateChartObject}}
  as |fsm|>
</StateMachine>
```

`<StateMachine />` is a renderless component that eases rendering of different states
from within templates using XState State Machine and Statechart objects.

**Please note**: This component is currently a gradual replacement for
StateChart, which has a less ergonmic interface. Guard and Action component are
currently omitted due to a preference to use entries to define those instead of
components (which is WIP)

### Arguments

| Argument/Attribute | Type | Default | Description |
| --- | --- | --- | --- |
| `chart` | `object` |  | An xstate statechart/state machine object |
| `initial` | `String` | The initial value of the state chart itself | The initial state of the machine/chart (defaults to whatever is defined on the object itself) |

The component currently yields 1 contextual components:

- `<fsm.State />`: Used for rendering matching certain states ([also see State Component](../state/README.mdx))

and 2 further objects:

- `fsm.dispatch`: An action to dispatch an xstate event
- `fsm.state`: The state object itself for usage in the `state-matches` helper

### Example

```hbs
<StateMachine
  @chart={{xstateStateChartObject}}
  as |fsm|>
    <fsm.State @matches="idle">
      Currently Idle
    </fsm.State>
    <fsm.State @matches="loading">
      Currently Loading
    </fsm.State>
    <fsm.State @matches={{array 'loading' 'idle'}}>
      Idle and loading
      <button disabled={{state-matches fsm.state "loading"}} onclick={{action fsm.dispatch "START"}}>Load</button>
    </fsm.State>
</StateMachine>
```

### See

- [Component Source Code](./index.js)
- [Template Source Code](./index.hbs)

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