This help topic is for R version 2.9.0. For the current version of R, try https://stat.ethz.ch/R-manual/R-patched/library/methods/html/selectSuperClasses.html
selectSuperClasses {methods}R Documentation

Super Classes (of Specific Kinds) of a Class

Description

Return superclasses of ClassDef, possibly only non-virtual or direct or simple ones.

These functions are designed to be fast, and consequently only work with the contains slot of the corresponding class definitions.

Usage

selectSuperClasses(Class, dropVirtual = FALSE, namesOnly = TRUE,
                   directOnly = TRUE, simpleOnly = directOnly,
                   where = topenv(parent.frame()))

.selectSuperClasses(ext, dropVirtual = FALSE, namesOnly = TRUE,
                    directOnly = TRUE, simpleOnly = directOnly)

Arguments

Class

name of the class or (more efficiently) the class definition object (see getClass).

dropVirtual

logical indicating if only non-virtual superclasses should be returned.

namesOnly

logical indicating if only a vector names instead of a named list class-extensions should be returned.

directOnly

logical indicating if only a direct super classes should be returned.

simpleOnly

logical indicating if only simple class extensions should be returned.

where

(only used when Class is not a class definition) environment where the class definition of Class is found.

ext

for .selectSuperClasses() only, a list of class extensions, typically getClassDef(..)@contains.

Value

a character vector (if namesOnly is true, as per default) or a list of class extensions (as the contains slot in the result of getClass).

Note

The typical user level function is selectSuperClasses() which calls .selectSuperClasses(); i.e., the latter should only be used for efficiency reasons by experienced useRs.

See Also

is, getClass; further, the more technical class classRepresentation documentation.

Examples

setClass("Root")
setClass("Base", contains = "Root", representation(length = "integer"))
setClass("A", contains = "Base", representation(x = "numeric"))
setClass("B", contains = "Base", representation(y = "character"))
setClass("C", contains = c("A", "B"))

extends("C")   #-->  "C"  "A" "B"  "Base" "Root"
selectSuperClasses("C") # "A" "B"
selectSuperClasses("C", direct=FALSE) # "A" "B"  "Base"  "Root"
selectSuperClasses("C", dropVirt = TRUE, direct=FALSE)# ditto w/o "Root"

[Package methods version 2.9.0 ]