如何正确记录 S4“[”和“[<-“使用氧气的方法？

Question

下面我发布了一个小示例，我想在其中编写文档 S4 类的 “[“ 方法。有人知道如何使用 roxygen 和 S4 正确记录通用 "[" 的方法吗？
构建后检查包时我收到警告（见下文）。

#' An S4 class that stores a string.
#' @slot a contains a string
#' @export
setClass("testClass", 
         representation(a="character"))

#' extract method for testClass
#'
#' @docType methods
#' @rdname extract-methods
setMethod("[", signature(x = "testClass", i = "ANY", j="ANY"),
         function (x, i, j, ..., drop){
             print("void function")
         }
)

包裹检查摘录：

* checking for missing documentation entries ... WARNING
Undocumented S4 methods:
  generic '[' and siglist 'testClass'
All user-level objects in a package (including S4 classes and methods)
should have documentation entries.
See the chapter 'Writing R documentation files' in manual 'Writing R Extensions'.

Answer 1

我终于或多或少弄清楚了。至少现在可以用了：

#' An S4 class that stores a string.
#' @slot a contains a string
#' @export
setClass("testClass", 
     representation(a="character"))

#' extract parts of testClass
#'
#' @name [
#' @aliases [,testClass-method
#' @docType methods
#' @rdname extract-methods
#'
setMethod("[", signature(x = "testClass", i = "ANY", j="ANY"),
    function (x, i, j, ..., drop){
       print("void function")
    }
)

Answer 2

从 roxygen2 > 3.0.0 开始，您不再需要解决方法，只需要：

#' Extract parts of testClass.
#'
setMethod("[", signature(x = "testClass", i = "ANY", j="ANY"),
  function (x, i, j, ..., drop){
    print("void function")
  }
)

Answer 3

就其价值而言，在替换功能的情况下，您将需要如下所示的内容：

#' An S4 class that stores a list.
#' @export
    setClass("testClass", 
      representation(a="list"))

#' extract parts of testClass
#'
#' @name [
#' @aliases [,testClass-method
#' @docType methods
#' @rdname extract-methods
setMethod("[", signature(x = "testClass", i = "ANY", j="ANY"),
  function (x, i, j, ..., drop) {
     x@a[i]
  }
)

#' replace names of testClass
#'
#' @name [
#' @aliases [<-,testClass-method
#' @docType methods
#' @rdname extract-methods
setReplaceMethod("names", signature(x = "testClass", value = "ANY"), definition = function (x, value) {
  names(x@a) <- value
  x
})