Partial matching of function argument
I know that for a list, partial matching is done when indexing using the basic operators $ and [[ . For example: ll <- list(yy=1) ll$y [1] 1 But I am still an R newbie and this is new for me, partial matching of function arguments: h <- function(xx=2)xx h(x=2) [1] 2 I want to understand how this works. What is the mechanism behind it? Does this have any side effects? I want understand how can someone test if the xx argument was given? Edit after Andrie comment: Internally R uses pmatch algorithm to match argument, here an example how this works: pmatch("me", c("mean", "median", "mode")) #