How to match many combinations of function arguments in R?

Can we create a 2-dimensional array for matching combinations of two function arguments?

For example, if I write a function with 1 argument (in addition to data input argument):

choose_procedure <- function(x, what_to_do) {
  switch(what_to_do,
         "mean"   = {...}, # mean(x) or mean(x, na.rm = TRUE) or weighted.mean(x)
         "median" = {...}, # median(x)
         "square" = {...}, # x * x or x ^ 2
         "unique" = {...}, # unique(x)
         "log"    = {...}  # log(x) or log10(x)
  )
}

I added inline comments to imply that there could be more than one choice per what_to_do input.

When what_to_do = "mean", should it be mean(x, na.rm = TRUE) or mean(x, na.rm = FALSE)? Likewise, when what_to_do = "log", should it be log(x) or log10(x)? Etc.

To handle this, I thought to introduce another argument to choose_procedure(), called "scenario". So if the call to choose_procedure() is:

choose_procedure(x = mtcars$mpg, what_to_do = "log", scenario = "A")

Then it would execute log(mtcars$mpg).
But if the call is

choose_procedure(x = mtcars$mpg, what_to_do = "log", scenario = "B")

then it would execute log10(mtcars$mpg).

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An example with just "log" and "scenario" describes a 2x2 array:

• "what_to_do" has 2 options: log() or log10()
• "scenario" has two options: "A" or "B"

Clearly, this could be handled with 4 if-statements (one for each combination), but will become very difficult to program if we have more combinations (as in choose_procedure() example I opened with).

So I have two questions:

1. I'm looking for a setup that could be extended to potentially any n × n array.
2. In fact, maybe there's a way to generalize to more than n × n? For example, if we have 3 arguments: "what_do_to", "scenario", "sub_scenario". Etc.