setMethodS3 {R.oo}R Documentation

Creates a method for a class using S3/UseMethod style

Description

Creates a method for a class using S3/UseMethod style. A function with name name.class will be set to definition. The method will get the modifiers specified by modifiers. If there exists no generic function for this method, it will be created automatically.

Usage

## Default S3 method:
setMethodS3(name, class="default", definition, private=FALSE, protected=FALSE, static=FALSE, abstract=FALSE, trial=FALSE, deprecated=FALSE, envir=parent.frame(), overwrite=TRUE, conflict=c("warning", "error", "quiet"), createGeneric=TRUE, appendVarArgs=TRUE, enforceRCC=TRUE, ...)

Arguments

name The name of the method.
class The class for which the method should be defined. If class == "default" (or class == "ANY") a function with name name.default will be created.
definition The method defintion.
private, protected If private=TRUE, the method is declared private. If protected=TRUE, the method is declared protected. In all other cases the method is declared public.
static If TRUE this method is defined to be static, otherwise not. Currently this has no effect expect as an indicator.
abstract If TRUE this method is defined to be abstract, otherwise not. Currently this has no effect expect as an indicator.
trial If TRUE this method is defined to be a trial method, otherwise not. A trial method is a method that is introduced to be tried out and it might be modified, replaced or even removed in a future release. Some people prefer to call trial versions, beta version. Currently this has no effect expect as an indicator.
deprecated If TRUE this method is defined to be deprecated, otherwise not. Currently this has no effect expect as an indicator.
envir The environment for where this method should be stored.
overwrite If TRUE an already existing method with the same name (and of the same class) will be overwritten, otherwise not.
conflict If a method already exists with the same name (and of the same class), different actions can be taken. If "error", an exception will be thrown and the method will not be created. If "warning", a warning will be given and the method will be created, otherwise the conflict will be passed unnotice.
createGeneric If TRUE, a generic S3/UseMethod function is defined for this method.
enforceRCC If TRUE, only class names following the R Coding Convention is accepted. If the RCC is violated an RccViolationException is thrown.
appendVarArgs If TRUE, argument ... is added with a warning, if missing. For special methods such as $ and [[, this is never done. This will increase the chances that the method is consistent with a generic function with many arguments and/or argument ....
... Not used.

Author(s)

Henrik Bengtsson http://www.braju.com/R/

See Also

To define a class, see setConstructorS3(). For a thorough example of how to use this method see Object. For information about the R Coding Conventions, see RccViolationException. For more information about UseMethod() see methods.

Examples

 ######################################################################
# Example 1
######################################################################
setMethodS3("foo", "default", function(x, ...) {
  cat("In default foo():\n");
  print(x, ...);
})

setMethodS3("foo", "character", function(s, ...) {
  cat("In foo() for class 'character':\n");
  print(s, ...);
})

# The generic function is automatically created!
print(foo)

foo(123)
foo("123")

######################################################################
# Example 2
#
# Assume that in a loaded package there is already a function bar(),
# but you also want to use the name 'bar' for the character string.
# It may even be the case that you do not know of the other package,
# but your users do!
######################################################################
# bar() in other package
bar <- function(x, y, ...) {
  cat("In bar() of 'other' package.\n");
}

# Your defintion; will redefine bar() above to bar.default().
setMethodS3("bar", "character", function(object, ...) {
  cat("In bar() for class 'character':\n");
  print(object, ...);
})

bar(123)
bar("123")



 ## Not run: For a complete example see help(Object).

[Package R.oo version 1.0.3 Index]