Best way for a function to accept alternative inputs

[xguardi]

Hello!
I was wondering which is the best way to implement a function that accept two types of inputs. Let's say I have the function:

foo <- function(param1, param2, param3){}

but also would like to pass those same params via config file (say a yaml file) for convenience:

foo <- function(file) {}

Thanks!

Xavi.

[nirgrahamuk]

My approach with this functionality would be to define foo. Then define a different function, perhaps foo_from_file that reads the file and calls foo in turn.