lazy duplicate value when setting as attribute
shallow copy for class<-
shallow copy dimnames<-
shallow copy attributes<-
shallow copy attr<-
lazy duplicate value to slot<-
shallow copy when getting @.Data
shallow copy in replacements by byte code evaluator
shallow copy during various subassignments
lazy copy value in subassignments
lazy copy elements during list repetition
declare lazy_copy
lazy duplicate apply results
lazy duplicate when combining lists
lazy duplicate when carrying over dimnames
lazy duplicate names in mget()
lazy duplicate when attaching objects
lazy duplicate when converting environments to lists
lazy duplicate result of eapply
shallow copy in asS4