[R] Evaluation of variable assigned to a function name

[carol white]

Hi,
I have defined a function (my.func) which is used as parameter (f) of another 
function. As I want to give the user the possibility to define his own function 
instead of my.func, how can I find out if in other functions, the parameter f 
has the my.func value (if the user has defined a new function or not)? 


Moreover, I think I should impose to the user to use another function name than 
my.func for this (?). Or a boolean variable is better to be used to indicate if 
my function (my.func) or user-defined function is used?

Thanks

Carol