selectSuperClasses 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  | 
| 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  | 
| ext | for  | 
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", slots = c(length = "integer"))
setClass("A", contains = "Base", slots = c(x = "numeric"))
setClass("B", contains = "Base", slots = c(y = "character"))
setClass("C", contains = c("A", "B"))
extends("C")   #-->  "C"  "A" "B"  "Base" "Root"
selectSuperClasses("C") # "A" "B"
selectSuperClasses("C", directOnly=FALSE) # "A" "B"  "Base"  "Root"
selectSuperClasses("C", dropVirtual=TRUE, directOnly=FALSE)# ditto w/o "Root"
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Licensed under the GNU General Public License.