Recall {base} | R Documentation |
Recall
is used as a placeholder for the name of the function
in which it is called. It allows the definition of recursive
functions which still work after being renamed, see example below.
Recall(...)
... |
all the arguments to be passed. |
Recall
will not work correctly when passed as a function
argument, e.g. to the apply
family of functions.
do.call
and call
.
local
for another way to write anonymous recursive functions.
## A trivial (but inefficient!) example:
fib <- function(n)
if(n<=2) { if(n>=0) 1 else 0 } else Recall(n-1) + Recall(n-2)
fibonacci <- fib; rm(fib)
## renaming wouldn't work without Recall
fibonacci(10) # 55