setClass
Define or Re-Define a Class of Objects
Description
Define a new class or re-define an existing class.
Usage
setClass(Class, representation = list(), prototype = NULL,
contains = character(), validity = NULL, access = list(),
where = topenv(parent.frame()), version = .newExternalptr(),
sealed = FALSE, package = getPackageName(where),
S3methods = FALSE, slots)
Arguments
| Class |
a character string name of the class to be defined.
|
| representation |
the representation for the class, including slot names and classes, and any contained
classes. If representation is given, it should be a class representation
(for example, a call to the function representation), although the name of
a single class is a valid short form.
|
| prototype |
the object to be used as the initial prototype. The function new
takes this object and sets its class to Class.
|
| contains |
a string vector of class names for the superclasses of this new class.
|
| validity |
an optional function of one argument for testing the validity of an object from the class.
It should return TRUE if its argument is a valid object from Class,
or a character string describing the problem otherwise. This is called by the
validObject function, which is called from new().
|
| access |
this argument is unimplemented, and a warning is generated if it is given.
|
| where |
this argument is unimplemented, and a warning is generated if it is given.
|
| version |
this argument is unimplemented, and a warning is generated if it is given.
|
| sealed |
this argument is unimplemented, and a warning is generated if it is given.
|
| package |
this argument is unimplemented, and a warning is generated if it is given.
|
| S3methods |
this argument is unimplemented, and a warning is generated if it is given.
|
| slots |
a list of strings or a character vector, specifying the slots for this class.
The names of the list or vector are the slot names, and the elements are the slot classes.
If an element has no name, the value is used as the slot name, and the class is "ANY".
If this argument and the representation argument are both specified, this produces an error.
|
Value
returns a function of class classGeneratorFunction, which can be called to create an object of the class.
This is similar to calling the new function.
See Also
Examples
## a class with two numeric slots
setClass("track", representation(x="numeric", y="numeric"))
## a class extending "matrix", with one new slot, and a validity method
setClass("tsMatrix", representation("matrix", tsp = "numeric"),
validity = function(x) nrow(x) == length(x@tsp))
## a class extending "tsMatrix" with no additional slots
setClass("tsMatrix2", "tsMatrix")
## using the 'slots' argument to specify slots
setClass("track2", slots=c(x="numeric", y="numeric"))