Change default arguments of an R function at runtime

Question

Is it possible to change the default values of formal parameters in an R function at runtime?

Let\'s assume, we have the function

f <- function(x=1) {         


        

Answer 1

As the Defaults package is no longer available from CRAN, you can use default.

As an example:

x <- list(a = 1, b = 2, c = 3)
default::default(unlist) <- list(use.names = FALSE)
unlist(x)
#> [1] 1 2 3

unlist <- default::reset_default(unlist)
unlist(x)
#> a b c 
#> 1 2 3

Created on 2019-03-22 by the reprex package (v0.2.0.9000).