The variable the value of the call id is assigned to, following every call that hands the value on (see handedOn) up to the assignment. A value used by anything else, as in f(mutate(df)), is assigned to nothing.
id
f(mutate(df))
Optional
The variable the value of the call
idis assigned to, following every call that hands the value on (see handedOn) up to the assignment. A value used by anything else, as inf(mutate(df)), is assigned to nothing.