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<p>
All scopes in IAML are instances of {@model Scope}, and a {@model Scope} may contain another {@model Scope} through a hierarchy of containment. A {@model Scope} may directly contain any number of {@model Scope}s. Every {@model Scope} will contain the pre-render lifecycle {@model Event}s {@event onAccess} (through {@model Accessible}) and {@event onInit}.
</p>

<p>
When a {@model Scope} is rendered, the lifecycle events for that {@model Scope} must be executed in the following order. If a failure occurs during this process, the current lifecycle execution process is cancelled and the <i>failure handler</i> for the current {@model Scope} is executed. If an {@model ECARule} is executed which must redirect the user to another {@model Frame}, the current lifecycle execution process is cancelled.
</p>

<ol>
  <li>If this {@model Scope} is contained by a parent {@model Scope}, then the pre-render lifecycle events for that parent {@model Scope} must be triggered.
  <li>If this {@model Scope} has not yet been <i>initialised</i> according to the storage semantics of that {@model Scope}, then the {@event onInit} {@model Event} is triggered.
  <li>The {@event onAccess} {@model Event} is triggered.
  <li>All entry {@model Gate}s contained within this {@model Scope} are sorted according to their {@model Gate#name}. The <i>access semantics</i> of each entry {@model Gate} are then executed.
  <li>All exit {@model Gate}s contained within this {@model Scope} are sorted according to their {@model Gate#name}. The <i>access semantics</i> of each exit {@model Gate} are then executed.
  <li>The {@model Scope} is then rendered.
</ol>

<h3>Failure Handler</h3>
<!--index failure handlers-->

<p>
An outgoing {@model ECARule} from a particular {@model Scope} with the {@model ECARule#name} "<code>fail</code>" is defined as a <i>failure handler</i> for the given scope. If an error occurs during the execution of the given {@model Scope} -- for example, an {@model Operation} fails -- then the failure handler for that {@model Scope} is executed according to the execution semantics of the {@model ECARule}.
</p>

<p>
If the current {@model Scope} does not define a <i>failure handler</i>, then the <i>failure handler</i> of the containing {@model Scope} is used as the failure handler. If an exception is not caught through the containment hierarchy of {@model Scope}s, then the exception is caught by the runtime environment and the web application will display a runtime error.
</p>