Singleton manipulation functions — singleton

Functions for manipulating singleton() objects in tag hierarchies. Intended for framework authors.

surroundSingletons(ui)

takeSingletons(ui, singletons = character(0), desingleton = TRUE)

Arguments

ui: Tag object or lists of tag objects. See builder topic.
singletons: Character vector of singleton signatures that have already been encountered (i.e. returned from previous calls to takeSingletons).
desingleton: Logical value indicating whether singletons that are encountered should have the singleton attribute removed.

Value

surroundSingletons preprocesses a tag object by changing any singleton X into X'

where sig is the sha1 of X, and X' is X minus the singleton attribute.

takeSingletons returns a list with the elements ui (the processed tag objects with any duplicate singleton objects removed) and singletons (the list of known singleton signatures).