Functions for manipulating singleton() objects in tag
hierarchies. Intended for framework authors.
surroundSingletons(ui)takeSingletons(ui, singletons = character(0), desingleton = TRUE)
surroundSingletons preprocesses a tag object by changing any
singleton X into <!--SHINY.SINGLETON[sig]-->X'<!--/SHINY.SINGLETON[sig]-->
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).
Tag object or lists of tag objects. See builder topic.
Character vector of singleton signatures that have already
been encountered (i.e. returned from previous calls to
takeSingletons).
Logical value indicating whether singletons that are encountered should have the singleton attribute removed.