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Writings functions (procedures) for data.table objects
I have a question concerning by-value/by-reference. data.table bring by-reference data.table<- and :=, but what about functions ?
DT <- data.table(a=c(1L,2L),b=c("foo","fii"));
f <- function(table){ table[,add:=1L]; };
f(DT); # would 0 or 1 copy of DT be performed here ?
R) DT
a b add
1: 1 foo 1
2: 2 fii 1
My understanding is that is using a function should imply a copy by value, but is it so ? Regards
