Dispose this object.
Whether the expression is satisfied. If context
provided, the service will attempt to retrieve a context object associated with that element.
a Set of the keys used by the given expression
or undefined
if none are used or the expression cannot be parsed.
Set or modify a value in the service's context.
Creates a temporary context that will use the values
passed in when evaluating callback
callback
must be synchronous.
Creates a child service with a separate context scoped to the HTML element passed in. Useful for e.g. setting the {view} context value for particular widgets.