class {base} | R Documentation |
R possesses a simple generic function mechanism which can be used for an object-oriented style of programming. Method despatch takes place based on the class of the first argument to the generic function.
An R “object” is a data object which has a class
attribute.
A class attribute is a vector of character strings giving the names of
the classes which the object “inherits” from. When a generic
function fun
is applied to an object with class attribute
c("first", "second")
, the system searches for a function called
fun.first
and, if it finds it, applies it to the object. If no
such function is found, a function called fun.second
is tried.
If no class name produces a suitable function, the function
fun.default
is used.
The function class
prints the vector of names of classes an
object inherits from. Correspondingly, class<-
sets the
classes an object inherits from.
unclass
returns (a copy of) its argument with its class
information removed.
inherits
indicates whether its first argument inherits from a
class with name equal to its second argument.
class(x)
class(x) <- names
unclass(x)
inherits(x, name)
UseMethod
, NextMethod
.