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AttachedBehaviorHTMLDirectiveA directive that attaches special behavior to an element via a custom attribute.
AttributeDefinitionAn implementation of Accessor that supports reactivity, change callbacks, attribute reflection, and type conversion for custom elements.
BindingBehaviorA behavior that updates content and attributes based on a configured BindingDirective.
ChildrenBehaviorThe runtime behavior for child node observation.
ControllerControls the lifecycle and rendering of a FASTElement.
CSSDirectiveDirective for use in css().
ElementStylesRepresents styles that can be applied to a custom element.
ExecutionContextProvides additional contextual information available to behaviors and expressions.
FASTElementDefinitionDefines metadata for a FASTElement.
HTMLBindingDirectiveA directive that configures data binding to element content and attributes.
HTMLDirectiveInstructs the template engine to apply behavior to a node.
HTMLViewThe standard View implementation, which also implements ElementView and SyntheticView.
PropertyChangeNotifierAn implementation of Notifier that allows subscribers to be notified of individual property changes on an object.
RefBehaviorThe runtime behavior for template references.
RepeatBehaviorA behavior that renders a template for each item in an array.
RepeatDirectiveA directive that configures list rendering.
SlottedBehaviorThe runtime behavior for slotted node observation.
SubscriberSetAn implementation of Notifier that efficiently keeps track of subscribers interested in a specific change notification on an observable source.
TargetedHTMLDirectiveA HTMLDirective that targets a named attribute or property on a node.
ViewTemplateA template capable of creating HTMLView instances or rendering directly to DOM.


attr(config)Decorator: Specifies an HTML attribute.
attr(target, prop)Decorator: Specifies an HTML attribute.
children(propertyOrOptions)A directive that observes the childNodes of an element and updates a property whenever they change.
compileTemplate(template, directives)Compiles a template and associated directives into a raw compilation result which include a cloneable DocumentFragment and factories capable of attaching runtime behavior to nodes within the fragment.
css(strings, values)Transforms a template literal string into styles.
cssPartial(strings, values)Transforms a template literal string into partial CSS.
customElement(nameOrDef)Decorator: Defines a platform custom element based on FASTElement.
elements(selector)Creates a function that can be used to filter a Node array, selecting only elements.
enableArrayObservation()Enables the array observation mechanism.
html(strings, values)Transforms a template literal string into a renderable ViewTemplate.
observable(target, nameOrAccessor)Decorator: Defines an observable property on the target.
ref(propertyName)A directive that observes the updates a property with a reference to the element.
repeat(itemsBinding, templateOrTemplateBinding, options)A directive that enables list rendering.
slotted(propertyOrOptions)A directive that observes the assignedNodes() of a slot and updates a property whenever they change.
volatile(target, name, descriptor)Decorator: Marks a property getter as having volatile observable dependencies.
when(binding, templateOrTemplateBinding)A directive that enables basic conditional rendering in a template.


AccessorRepresents a getter/setter property accessor on an object.
BehaviorRepresents and object that can contribute behavior to a view or element's bind/unbind operations.
BindingObserverEnables evaluation of and subscription to a binding.
CaptureTypeA marker interface used to capture types when interpolating Directive helpers into templates.
ChildListBehaviorOptionsThe options used to configure child list observation.
CompilationResult(BETA) The result of compiling a template and its directives.
ElementViewA View representing DOM nodes specifically for rendering the view of a custom element.
ElementViewTemplateA template capable of creating views specifically for rendering custom elements.
FASTElementRepresents a custom element based on the FASTElement infrastructure.
NodeBehaviorFactoryA factory that can create a Behavior associated with a particular location within a DOM fragment.
NodeBehaviorOptionsOptions for configuring node observation behavior.
NotifierProvides change notification for a source object.
ObservationRecordA record of observable property access.
PartialFASTElementDefinitionRepresents metadata configuration for a custom element.
RepeatOptionsOptions for configuring repeat behavior.
SlottedBehaviorOptionsThe options used to configure slotted node observation.
SpliceRepresents a set of splice-based changes against an Array.
StyleTargetA node that can be targeted by styles.
SubscriberImplemented by objects that are interested in change notifications.
SubtreeBehaviorOptionsThe options used to configure subtree observation.
SyntheticViewA view representing a range of DOM nodes which can be added/removed ad hoc.
SyntheticViewTemplateA template capable of rendering views not specifically connected to custom elements.
ValueConverterRepresents objects that can convert values to and from view or model representations.
ViewRepresents a collection of DOM nodes which can be bound to a data source.


$globalA reference to globalThis, with support for browsers that don't yet support the spec.
booleanConverterA ValueConverter that converts to and from boolean values.
defaultExecutionContextThe default execution context used in binding expressions.
FASTElementA minimal base class for FASTElements that also provides static helpers for working with FASTElements.
nullableNumberConverterA ValueConverter that converts to and from number values.
ObservableCommon Observable APIs.

Type Aliases

Type AliasDescription
AttachedBehaviorTypeDescribes the shape of a behavior constructor that can be created by an AttachedBehaviorHTMLDirective.
AttributeConfigurationMetadata used to configure a custom attribute's behavior.
AttributeModeThe mode that specifies the runtime behavior of the attribute.
BindingThe signature of an arrow function capable of being evaluated as part of a template binding update.
CallableRepresents a callable type such as a function or an object with a "call" method.
ChildrenBehaviorOptionsThe options used to configure child/subtree node observation.
ComposableStylesRepresents styles that can be composed into the ShadowDOM of a custom element.
ConstructableAllows for the creation of Constructable mixin classes.
DecoratorAttributeConfigurationMetadata used to configure a custom attribute's behavior through a decorator.
ElementsFilterElements filter function type.
ElementStyleFactoryCreates an ElementStyles instance for an array of ComposableStyles.
GlobalThe platform global type.
TemplateValueRepresents the types of values that can be interpolated into a template.
TrustedTypesEnables working with trusted types.
TrustedTypesPolicyA policy for use with the standard trustedTypes platform API.