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selectSuperClasses {methods}

Super Classes (of Specific Kinds) of a Class
Package: 
methods
Version: 
R 3.0.1

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.

Values

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"

Documentation reproduced from R 3.0.1. License: GPL-2.