Abstract: The subject technology discloses configurations for receiving an indication of user activity from a first user with respect to a post, wherein the post includes content shared by a second user, in response to receiving the indication, an activity post providing an indication of the user activity with respect to the post is created, the activity post including the content, and a set of users that the activity post is visible to are identified, the set of users comprising one or more users selected from users associated with the first user in a social graph, the activity post is provided for display to the set of users in response to the indication.

Abstract: A hierarchically structured electronic document includes a parent node, a first and a second child of the parent node. The first child is configured as a named role child, the named role child having a first child component, the named role child specifying a relationship between the first child component and the parent node. The second child is configured as an index role child and has a plurality of second child components. The index role child specifies that all second child components are index children. The second child components collectively define and are configured to be rendered in the order in which the second child components appear under the second child. Collisions between named role and index children are avoided as the document includes a role (either a name role or an index role) between the parent and each child of the parent that is at the same hierarchical level.

Abstract: Every attribute or property of an element in a declarative environment such as XML may be bound to an external data source or defaulted when binding fails to resolve. The failure to resolve the binding may be caused by an incorrect key or an unavailable or incorrect data source. The default attribute may be hard coded or may point to another data source where a default value of the attribute may be found.