R: Get an S3 Method

getS3method {utils} | R Documentation

## Get an S3 Method

### Description

Get a method for an S3 generic, possibly from a namespace or the generic's registry.

### Usage

    getS3method(f, class, optional = FALSE, envir = parent.frame())

### Arguments

`f` | character: name of the generic.
`class` | character: name of the class.
`optional` | logical: should failure to find the generic or a method be allowed?
`envir` | the `environment` in which the method and its generic are searched first.

### Details

S3 methods may be hidden in namespaces, and will not then be found by `get`: this function can retrieve such functions, primarily for debugging purposes.

Further, S3 methods can be registered on the generic when a namespace is loaded, and the registered method will be used if none is visible (using namespace scoping rules).

It is possible that which S3 method will be used may depend on where the generic `f` is called from: `getS3method` returns the method found if `f` were called from the same environment.

### Value

The function found, or `NULL` if no function is found and `optional = TRUE`.

### See Also

`methods`, `get`, `getAnywhere`

### Examples

    require(stats)
    exists("predict.ppr") # false
    getS3method("predict", "ppr")

[Package utils version 3.5.1 Index]