函数重载?

Here is my attempt:

这是我的尝试:

MyClass = setRefClass("MyClass", fields = c("x", "y"))
MyClass$methods(
    myadd = function() {
        x + y
    }
)
MyClass$methods(
    myadd = function(n) {
        x + y + n
    }
)
MyClass$methods(
    initialize = function(xinit, yinit) {
        x <<- xinit
        y <<- yinit
    }
)

myobj = MyClass(2, 3)
myobj$myadd()
MyClass = setRe